Platform and method of operating for integrated end-to-end fully self-aligned interconnect process

ABSTRACT

A method for forming a fully self-aligned via is provided. A workpiece having a pattern of features in a dielectric layer is received into a common manufacturing platform. Metal caps are deposited on the metal features, and a barrier layer is deposited on the metal caps. A first dielectric layer is added to exposed dielectric material. The barrier layer is removed and an etch stop layer is added on the exposed surfaces of the first dielectric layer and the metal caps. Additional dielectric material is added on top of the etch stop layer, then both the additional dielectric material and a portion of the etch stop layer are etched to form a feature to be filled with metal material. An integrated sequence of processing steps is executed within one or more common manufacturing platforms to provide controlled environments. Transfer modules transfer the workpiece between processing modules within and between controlled environments.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims the benefit of U.S. ProvisionalApplication No. 62/645,685, filed on Mar. 20, 2018, entitled “SubstrateProcessing Tool with Integrated Metrology and Method of Using,” U.S.Provisional Application No. 62/787,607, filed on Jan. 2, 2019, entitled“Self-Aware and Correcting Heterogeneous Platform incorporatingIntegrated Semiconductor Processing Modules and Method for using same,”U.S. Provisional Application No. 62/787,608, filed on Jan. 2, 2019,entitled “Self-Aware and Correcting Heterogeneous Platform incorporatingIntegrated Semiconductor Processing Modules and Method for using same,”and U.S. Provisional Application No. 62/788,195, filed on Jan. 4, 2019,entitled “Substrate Processing Tool with Integrated Metrology and Methodof using,” which is incorporated herein by reference in its entirety.

BACKGROUND OF THE INVENTION Field of Invention

The present invention relates to a processing platform and methods forsemiconductor processing using the platform, and more particularly to amethod of forming a fully self-aligned via (FSAV).

Description of Related Art

Recess shape formation techniques have been used for formation of viason transistor wafers, and the like. Dimension shrinkage is one of thedriving forces in the development of integrated circuit processing. Byreducing the size dimensions, cost-benefit and device performance boostscan be obtained. This scalability creates inevitable complexity inprocess flow, especially on patterning techniques. As smallertransistors are manufactured, the critical dimension (CD) or resolutionof patterned features is becoming more challenging to produce,particularly in high volume. Self-aligned patterning needs to replaceoverlay-driven patterning so that cost-effective scaling can continue.Patterning options that enable reduced variability, extend scaling, andenhance CD and process control are needed in a high-volume manufacturingenvironment; however, it is getting extremely difficult to producescaled devices at reasonably low cost and high yield.

As devices are scaled to smaller and smaller features and techniques areimplemented to try and address the issues that result from scaling, itis important to monitor the fabrication process at various stages of theprocess flow to determine whether the feature attributes are withinspecification, and if not, to adjust the process to either bring theworkpiece within specification or to bring subsequently processedworkpieces within specification.

In conventional via fabrication, the process is performed using multipleseparate stand-alone tools for high-volume manufacturing. Wafers aresequentially loaded into one tool, subjected to one process step in thattool, then removed to ambient environment and placed in queue to beloaded into the next tool, and so on until the multiple steps of the viafabrication flow are complete. Time spent waiting in queue for each toolis referred to as Q-time, and high Q-times result in lower productionrates. Different operations in the process flow may take differentamounts of time such that throughput matching of tools is a productionchallenge.

Further, in conventional via fabrication, the distance fromcorner-to-corner of adjacent metal features may be too small for thesemiconductor to operate properly. For example, too small of a distancefrom corner-to-corner of adjacent metal features may result in thesemiconductor shorting in operation. Increasing the metal featurecorner-to-corner distance allows the semiconductor to successfullyoperate more consistently.

Each tool in the process flow may be part of a tool cluster. Forexample, five identical etch tools can be clustered in combination witha transfer tool so that 5 wafers can be etched concurrently at one stepof the process flow to enable high-volume production. The multiplicityof these cluster tools provides a benefit if a tool goes out of servicefor any reason. If 1 tool in a 5-tool cluster goes out of service for 1week, then production can continue, albeit at only 80% capacity. Thus,each stand-alone tool in the SAMP flow may be a cluster of identicaltools to prevent an out of service tool from shutting down productioncompletely, and clustering may be used to minimize throughput matchingchallenges.

Additionally, semiconductors with fully self-aligned vias improve thetime dependent dielectric breakdown (TDDB) of the semiconductor. TDDB isa reliability metric for the amount of time to breakdown dielectricmaterial under normal operating conditions (e.g., electric fieldexposure). TDDB performance can be optimized based on the device layout(e.g., dielectric material type, dielectric thickness, metal lineplacement with respect to the dielectric material) and operatingconditions (e.g. voltage, frequency) to maintain electrical isolationbetween metal features in a device. For example, repeated low-levelexposure to electric fields during normal operation may alter theelectrical properties of the dielectric material over a period of time.TDDB quantifies the amount of time for dielectric breakdown to occur.The fully self-aligned via techniques described herein may increase TDDBby altering the layout by increasing the distance between the vias andthe underlying metal lines. For example, the FSAV techniques canincrease isolation by narrowing the contact portion of the via toincrease the amount of dielectric material between the vias and adjacentmetal lines.

Thus, the conventional approach of using multiple separate stand-alonetools (single or clustered) for high-volume manufacturing can lead toissues including but not limited to Q-time oxidation (i.e., as thewafers sit between tools waiting for their turn in the next tool, theycan be subjected to oxidation from the ambient environment), defectivityfrom environmental exposure between tools, cost challenges due tothroughput matching difficulties, temporal tool drift (e.g., EPE), realtime chamber matching (e.g., yield and EPE), and lack of real-timeworkpiece measurement and process control. There is a need to addressthese and other issues, such as shorting of integrated circuits, toenable high-volume manufacturing with via fabrication techniques.

SUMMARY OF THE INVENTION

A method of preparing for a self-aligned via on a semiconductorworkpiece is provided using an integrated sequence of processing stepsexecuted on a common manufacturing platform hosting a plurality ofprocessing modules including one or more film-forming modules, one ormore etching modules, and one or more transfer modules. In oneembodiment, the integrated sequence of processing steps includesreceiving the workpiece into the common manufacturing platform, theworkpiece having a pattern of metal features in a dielectric layerwherein exposed surfaces of the metal features and exposed surfaces ofthe dielectric layer together define an upper planar surface. Next,metal caps are selectively deposited on the exposed surfaces of themetal features relative to the exposed dielectric material using one ofthe one or more of the film-forming modules. Then, a barrier layer isselectively formed on the metal caps, using one of the one or morefilm-forming modules, relative to the exposed dielectric material. Afirst dielectric material is selectively deposited on the exposedsurfaces of the dielectric layer using one of the one or morefilm-forming modules to form a recess pattern in the first dielectricmaterial, the selective deposition being based, at least in part, on adeposition rate of the first dielectric material being higher on theexposed surfaces than on the metal caps, the recess pattern comprising asidewall including a portion of the first dielectric material. Then, theworkpiece is treated to expose the metal caps at bottom surfaces of therecess pattern using one of the one or more etch modules. Next, an etchstop layer is deposited over the recess pattern using one of the one ormore film-forming modules. The integrated sequence of processing stepsis executed in a controlled environment within the common manufacturingplatform and without leaving the controlled environment, and wherein theone or more transfer modules are used to transfer the workpiece betweenthe plurality of processing modules while maintaining the workpiecewithin the controlled environment. Thereafter, one or more self-alignedvias can be formed on the semiconductor workpiece, such as using othermodules and/or common manufacturing platforms.

In another embodiment, the integrated sequence of processing stepsincludes receiving the workpiece into the common manufacturing platform,the workpiece having a pattern of metal features in a dielectric layerwherein exposed surfaces of the metal features and exposed surfaces ofthe dielectric layer together define an upper planar surface. Then, themetal features are selectively etched to form a recess pattern byrecessing the exposed surfaces of the metal features beneath the exposedsurfaces of the dielectric layer using one of the one or more etchingmodules. Next, an etch stop layer is deposited over the recess patternusing one of the one or more film-forming modules. The integratedsequence of processing steps is executed in a controlled environmentwithin the common manufacturing platform and without leaving thecontrolled environment, and wherein the one or more transfer modules areused to transfer the workpiece between the plurality of processingmodules while maintaining the workpiece within the controlledenvironment. Thereafter, one or more self-aligned vias can be formed onthe semiconductor workpiece, such as using other modules and/or commonmanufacturing platforms.

In yet another embodiment, the integrated sequence of processing stepsincludes receiving the workpiece into the common manufacturing platform,the workpiece having a pattern of metal features in a dielectric layerwherein exposed surfaces of the metal features and exposed surfaces ofthe dielectric layer together define an upper planar surface. Then,metal caps are selectively deposited on the exposed surfaces of themetal features relative to the exposed dielectric material using one ofthe one or more of the film-forming modules. Next, a recessed pattern ofdielectric material is selectively formed around the metal featuresrelative to the dielectric material, with the metal caps forming abottom surface of the recessed pattern, the metal caps being exposedfrom the top of the trench. Then, an etch stop layer is deposited overthe recess pattern using one of the one or more film-forming modules.The integrated sequence of processing steps is executed in a controlledenvironment within the common manufacturing platform and without leavingthe controlled environment, and wherein the one or more transfer modulesare used to transfer the workpiece between the plurality of processingmodules while maintaining the workpiece within the controlledenvironment. Thereafter, one or more self-aligned vias can be formed onthe semiconductor workpiece, such as using other modules and/or commonmanufacturing platforms.

In a related embodiment, the methods can be continued to includeobtaining real-time measurement data related to one or more attributesof the workpiece in a workpiece measurement region located within adedicated area of at least one of the one or more transfer modules orlocated within a metrology module(s) hosted on one or more commonmanufacturing platforms. And a remedial action can be implemented toameliorate the non-conformity when the measurement data indicates thenon-conformity is present on the workpiece.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the invention and,together with the general description of the invention given above, andthe detailed description given below, serve to describe the invention.

FIGS. 1A-1M are schematic cross-sectional diagrams illustrating oneembodiment of a fully self-aligned via formation method;

FIG. 2 is a flow chart diagram illustrating one embodiment of anintegrated process flow for fully self-aligned via formation;

FIG. 3 is a schematic diagram illustrating one embodiment of a commonmanufacturing platform for performing a fully self-aligned via formationmethod.

FIGS. 4A-4B are schematic cross-sectional diagram comparing conventionalfilled features with fully self-aligned via features;

FIGS. 5A-5K are schematic cross-sectional diagrams illustrating oneembodiment of a fully self-aligned via formation method; and

FIG. 6 is a flow chart diagram illustrating one embodiment of anintegrated process flow for fully self-aligned via formation.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Methods using an integrated platform for fully self-aligned viaformation are presented. However, one skilled in the relevant art willrecognize that the various embodiments may be practiced without one ormore of the specific details, or with other replacement and/oradditional methods, materials, or components. In other instances,well-known structures, materials, or operations are not shown ordescribed in detail to avoid obscuring aspects of various embodiments ofthe invention.

Similarly, for purposes of explanation, specific numbers, materials, andconfigurations are set forth in order to provide a thoroughunderstanding of the invention. Nevertheless, the invention may bepracticed without specific details. Furthermore, it is understood thatthe various embodiments shown in the figures are illustrativerepresentations and are not necessarily drawn to scale. In referencingthe figures, like numerals refer to like parts throughout.

Reference throughout this specification to “one embodiment” or “anembodiment” or variation thereof means that a particular feature,structure, material, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention butdoes not denote that it is present in every embodiment. Thus, thephrases such as “in one embodiment” or “in an embodiment” that mayappear in various places throughout this specification are notnecessarily referring to the same embodiment of the invention.Furthermore, the particular features, structures, materials, orcharacteristics may be combined in any suitable manner in one or moreembodiments. Various additional layers and/or structures may be includedand/or described features may be omitted in other embodiments.

Additionally, it is to be understood that “a” or “an” may mean “one ormore” unless explicitly stated otherwise.

Various operations will be described as multiple discrete operations inturn, in a manner that is most helpful in understanding the invention.However, the order of description should not be construed as to implythat these operations are necessarily order dependent. In particular,these operations need not be performed in the order of presentation.Operations described may be performed in a different order than thedescribed embodiment. Various additional operations may be performedand/or described operations may be omitted in additional embodiments.

As used herein, the term “substrate” means and includes a base materialor construction upon which materials are formed. It will be appreciatedthat the substrate may include a single material, a plurality of layersof different materials, a layer or layers having regions of differentmaterials or different structures in them, etc. These materials mayinclude semiconductors, insulators, conductors, or combinations thereof.For example, the substrate may be a semiconductor substrate, a basesemiconductor layer on a supporting structure, a metal electrode or asemiconductor substrate having one or more layers, structures or regionsformed thereon. The substrate may be a conventional silicon substrate orother bulk substrate comprising a layer of semi-conductive material. Asused herein, the term “bulk substrate” means and includes not onlysilicon wafers, but also silicon-on-insulator (“SOT”) substrates, suchas silicon-on-sapphire (“SOS”) substrates and silicon-on-glass (“SOG”)substrates, epitaxial layers of silicon on a base semiconductorfoundation, and other semiconductor or optoelectronic materials, such assilicon-germanium, germanium, gallium arsenide, gallium nitride, andindium phosphide. The substrate may be doped or undoped.

As used herein the term “workpiece” means a composition of materials orlayers formed on a substrate during one or more phases of asemiconductor device manufacturing process, the workpiece ultimatelycomprising the semiconductor device at a final stage of processing.

The present embodiments include methods for fully self-aligned viaformation that utilize one or more common manufacturing platforms inwhich multiple processing steps are performed on each of the commonmanufacturing platforms within their own controlled environment, forexample, without breaking vacuum between operations. An integratedend-to-end platform may include both etching modules and film-formingmodules and is configured to transfer a workpiece from one module toanother while maintaining the workpiece in a controlled environment,e.g., without breaking vacuum or leaving an inert gas protectiveenvironment, and thus avoiding exposure to an ambient environment. Anyfully self-aligned via formation process may include steps performed onthe common manufacturing platform, and the integrated end-to-endplatform will enable high-volume manufacturing at reduced cost withimprovement to yield, defectivity levels and EPE.

As used herein, a “film-forming module” refers to any type of processingtool for depositing or growing a film or layer on a workpiece in aprocess chamber. The film-forming module may be a single wafer tool, abatch processing tool, or a semi-batch processing tool. The types offilm deposition or growth that may be performed in the film-formingmodule include, by way of example and not limitation, chemical vapordeposition, plasma-enhanced or plasma-assisted chemical vapordeposition, atomic layer deposition, physical vapor deposition, thermaloxidation or nitridation, elevated temperature deposition, etc., and theprocess may be isotropic, anisotropic, conformal, selective, blanket,etc.

As used herein, an “etching module” refers to any type of processingtool for removing all or a portion of a film, layer, residue orcontaminant on a workpiece in a process chamber. The etching module maybe a single wafer tool, a batch processing tool, or a semi-batchprocessing tool. The types of etching that may be performed in theetching module include, by way of example and not limitation, chemicaloxide removal (COR), dry (plasma) etching, reactive ion etching, wetetching using immersion or non-immersion techniques, atomic layeretching, chemical-mechanical polishing, cleaning, ashing, lithography,etc., and the process may be isotropic, anisotropic, selective, etc.

As used herein, “module” generally refers to a processing tool with allof its hardware and software collectively, including the processchamber, substrate holder and movement mechanisms, gas supply anddistribution systems, pumping systems, electrical systems andcontrollers, etc. Such details of the modules are known in the art andtherefore not discussed herein.

As used herein, “controlled environment” as used herein refers to anenvironment in which the ambient atmosphere is evacuated and eitherreplaced with a purified inert gas or a low-pressure vacuum environment.A vacuum environment is well below atmospheric pressure and is generallyunderstood to be 10⁻⁵ Torr or less, for example 5×10⁻⁸ Torr or less.However, the controlled environment may include any sub-atmosphericpressure environment within the processing tool that is isolated fromambient air conditions or environments greater than atmosphericpressure. Further, the controlled environment within the processing toolis not required to be a constant pressure, or the same pressure, withineach portion of the processing tool. For example, pressure within thecontrolled environment may vary within each chamber of the processingtool at different times to enable different processing conditions withina respective chamber or minimize pressure differentials between two ormore chambers when substrates are transferred between chambers.

Reference is now made to the drawings, where like reference numeralsdesignate identical or corresponding parts throughout the several views.

FIGS. 1A-1M illustrate schematic cross-sectional diagrams illustratingone embodiment of a fully self-aligned via formation method for aworkpiece 100. FIG. 2 is a flow chart of a process flow 200corresponding to the method of FIGS. 1A-1M. FIG. 3 illustrates anembodiment of an arrangement of a first common manufacturing platform300 together with an ancillary module 350 and a second commonmanufacturing platform 360 of the invention that may be used forperforming process flow 200. FIGS. 4A and 4B are an illustration of aresulting benefit of the workpiece 100. The process flow 200 of FIG. 2and the first common manufacturing platform 300, second commonmanufacturing platform 360, and ancillary module 350 of FIG. 3 will bereferenced throughout the following sequential discussion of FIGS. 1A-1Min which workpiece 100 is described as it proceeds through a sequence ofprocessing steps.

In operation 202 of process flow 200 and as shown in FIG. 1A, aworkpiece 100 having a pattern of metal features 110 in an underlyinglayer 106 is provided into the first common manufacturing platform 300.The workpiece 100 includes the pattern of metal features 110 and theunderlying layer 106 positioned on the substrate 104. To those familiarin the current art, different schemes are known for creating a patternof metal features 110 on a substrate. For simplicity, workpiece 100 isdepicted with a substrate 104 having an underlying layer 106 thereon,although it may be understood that the structure on which the metalfeatures 110 are formed may be a multi-layer structure of which theunderlying layer 106 is just one of multiple layers.

The underlying layer 106 may be an oxide layer including silicon oxide,silicon dioxide, a carbon doped silicon oxide, a porous carbon dopedsilicon oxide, or some other oxide of silicon. In the case of a porousoxide, a pore sealing process may be performed prior to operation 204(not shown). Alternatively or in addition, the underlying layer 106 maybe a dielectric layer.

The metal features 110 may include, but is not limited to copper,ruthenium, cobalt, tungsten, or combinations thereof. Additionally, aliner layer 111 is included in the recessed feature along with the metalmaterial in the metal features 110. The liner layer 111 may includetantalum nitride, and inhibits the metal from contacting the oxideand/or dielectric material in the underlying layer 106. The liner layer111 may serve to bond the metal material in the metal feature 110 to theunderlying layer 106. Alternatively or in addition, the liner layer 111may serve to prevent the metal material in the metal feature 110 fromdiffusing into the underlying layer 106.

As shown in FIG. 3, a front end module (FEM) 302 or a transfer module310 a may be used to bring the workpiece into the controlled environmentof the first common manufacturing platform 300, which controlledenvironment is maintained throughout at least a portion of the processflow 200. The controlled environment may include a vacuum environment,where at least some operations in the process flow 200 are conducted insequence without breaking vacuum, or an inert gas atmosphere, or acombination thereof. A single transfer module may be coupled betweeneach processing module or tool, such as each of transfer modules 310 a,310 b shown in FIG. 3, or separate transfer modules may be used for eachtool transfer. Transfer modules 310 a-b may be collectively referred toherein as transfer modules 310 where appropriate. Where differentprocessing modules on the first common manufacturing platform 300require different controlled environments, such as different vacuumpressures or vacuum in one module followed by a module with inert gasatmosphere, multiple transfer modules 310 may be used where the transfermodules 310 assist in implementing the transitions between the differentcontrolled environments. While a single transfer module may be useful ina cluster-type tool where same-type processing modules are positioned ina circle around the transfer module, multiple transfer modules 310 maybe more appropriate in an end-to-end platform configuration withdifferent processing module types such as that depicted in FIG. 3.However, the embodiments herein do not preclude an end-to-end platformconfiguration that utilizes a single transfer module that is coupled toeach of the processing modules, or some configuration in between, forexample, a common transfer module for adjacent same-type processingmodules that are used in sequence.

A front-end module 302 may be used to load a cassette of workpieces (notshown), sequentially line up the workpieces and insert them into a loadlock, then into a transfer module 310 a in a controlled environment, andthe transfer module 310 a sequentially loads the workpieces into aprocessing module. In the first common manufacturing platform 300, inoperation 202, the workpiece 100, which has been received into thecontrolled environment, is loaded by the transfer module 310 a into afilm-forming module 320 a or 320 b hosted on the first commonmanufacturing platform 300. Film-forming modules 320 a, 320 b may becollectively referred to herein as film-forming modules 320 whereappropriate. Similarly, etching modules 330 a, 330 b may be collectivelyreferred to herein as etching modules 330 where appropriate. Similarly,metrology modules 312 a-d may be collectively referred to herein asmetrology modules 312 where appropriate. Similarly, cleaning modules 340a, 340 b may be collectively referred to herein as cleaning modules 340where appropriate.

Referring to FIGS. 1B, 2, and 3, in operation 204, in the film-formingmodule 320, a metal cap 112 is selectively deposited over the exposedsurface 108 of the metal features 110. The exposed surfaces 108 of themetal features 110 together with the upper surface of the underlyinglayer 106 form an upper planar surface of the workpiece 100. The metalcap 112 may include ruthenium, titanium, tungsten, molybdenum, orcobalt. The metal cap 112 selectively is deposited onto the exposedsurface 108 of the metal features 110 while simultaneously negligiblybonding to the exposed surface of the underlying layer 106. In oneembodiment, the selective application of the metal cap 112 may be based,at least in part, on the selectivity between the metal caps 112 and thedielectric material (e.g., underlying layer 106) being based, at leastin part, on a higher metal deposition rate on the metal features 110than on the dielectric material. In this way, the metal thickness on theexposed surface 108 of the metal features 110 will be thicker than themetal deposited on the dielectric material during one or more steps ofthe metal deposition process. In some instances, the selectivity betweenthe metal features 110 and the dielectric material may decrease as themetal cap 112 thickness increases due to larger amounts of metal on thedielectric material enables a higher metal deposition rate on thedielectric material. One approach to counter the reduced selectivity isto expose the workpiece to an metal etching process to remove any metalfrom the dielectric material during the metal cap deposition step. Themetal etch process may be implemented in one or more of the etchingmodules on the common manufacturing platform using a process known toany person of ordinary skill in the art of plasma etching in thesemiconductor industry.

In some embodiments, the selectivity between the metal features 110 andthe dielectric material can be improved by applying a pre-treatment tothe workpiece to alter a surface termination of the first dielectricmaterial, such that the difference in metal cap deposition rate betweenthe metal features 110 and the dielectric material is higher thanwithout the pre-treatment. In this embodiment, the common manufacturingplatform may include in one or more pre-treatment modules capable ofgenerating a gas or plasma treatment.

As shown in FIG. 3, the first common manufacturing platform 300 mayinclude two identical film-forming modules 320 a, 320 b on the same sideof the transfer module 310 a. Alternatively, the film-forming modules320 may be on opposite sides of the transfer module 310 a. By mirroringthe two sides of the platform 300, end-to-end processing can be achievedfor two workpieces concurrently, and if one film-forming module 320 goesout of service temporarily, the platform 300 can continue to operate, atleast at 50% capacity. In some examples, the metal caps 112 selectivityto the metal features 110 relative to the underlying layer 106 is atleast 10:1.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer modules 310 a and 310 b may be used to transfer theworkpiece 100 to the film-forming module 320 such as first film-formingmodule 320 a also hosted on the first common manufacturing platform 300,e.g., transfer module 310 a removes the workpiece 100 from firstfilm-forming module 320 a and transfers it to transfer module 310 b,which then may redeliver the workpiece 100 into the first film-formingmodule 320 a or to second film-forming module 320 b. Adjustments to thecontrolled environment may be made in transfer modules 310 a and 310 bif second film-forming module 320 b operates with different parametersthan first film-forming module 320 a, such as different vacuumpressures.

Referring to FIGS. 1C, 2, and 3, in operation 206, a barrier layer 114is deposited over the metal caps 112 in at least one of the film-formingmodules 320 to cover the metal caps 112. In some examples, the barrierlayer 114 includes a self-assembled monolayer (SAM). The barrier layer114 material has an affinity toward the metal caps 112, and thus thebarrier layer 114 selectively deposits to cover the metal caps 112relative to the underlying layer 106. In some examples, the barrierlayer 114 encases the metal caps 112 over the metal features 110 and maybe deposited in much smaller amounts on the dielectric material (e.g.,underlying layer 106) based, at least in part, on the selectivitybetween the metal cap and the dielectric material being based, at leastin part, on a higher barrier layer deposition rate on the metal caps 112than on the dielectric material. In one embodiment, the difference indeposition rate is derived from the barrier layer 114 material having ahigher affinity for the metal caps 112 than the dielectric material.

In some embodiments, the common manufacturing platform may include anetching module to remove the barrier layer 114, in certain instances,using a process known to any person of ordinary skill in the art ofplasma etching or semiconductor manufacturing.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 208, with reference to FIGS. 1D,2, and 3, a first dielectric layer 116 is selectively deposited onto theunderlying layer 106. At least due to repulsive interactions between thefirst dielectric layer 116 material and the barrier layer 114 material,the first dielectric layer 116 bonds less with the barrier layer 114relative to the underlying layer 106. As a result, the barrier layer 114shields the metal caps 112 from being exposed to the first dielectriclayer 116 material at least during deposition of the first dielectriclayer 116. The deposition of the first dielectric layer 116 may occur inany of the film-forming modules 320. For example, the deposition of thefirst dielectric layer 116 may occur in the same film-forming module 320as the deposition of the metal caps 112. Alternatively or in addition,the deposition of the first dielectric layer 116 may occur in adifferent film-forming module 320 than the deposition of the metal caps112. The first dielectric layer 116 is deposited in such a way as toform a recess pattern 118 in the first dielectric material 116 based, atleast in part, on the selective deposition process including two or moredeposition steps in which the dielectric material is layered to form thesidewalls 128 of the recessed pattern 118. For example, the selectivedeposition process may include two or more deposition steps which apply10 nm or less of the first dielectric material 116 on the workpiece. Inthis way, etching back the first dielectric layer 116 is avoided at thistime at least because the recessed pattern 118 naturally forms at leastdue to the barrier layer's 114 repulsion of the first dielectric layer116 material. Alternatively or in addition, the selective deposition ofthe first dielectric layer is based, at least in part, on a depositionrate of the first dielectric layer 116 material being higher on theexposed surfaces of the underlying layer 106 than on the barrier layer114. Each of the recessed pattern 118 features includes sidewalls 128.The sidewalls 128 include at least a portion of the first dielectriclayer 116 material. The first dielectric layer 116 material may includesilicon oxide, silicon dioxide, a carbon doped silicon oxide, a porouscarbon doped silicon oxide, or some other oxide of silicon. In someexamples, the first dielectric layer 116 material is the same as theunderlying layer 106 material. Alternatively, the first dielectric layer116 is a different material than the underlying later 106 material.

In some instances, as the thickness of the first dielectric materialincreases on the barrier layer 114, the selectivity between the barrierlayer 114 and the first dielectric material decreases impacting theprofile and step-height of the sidewall 128. However, selectivity may beimproved by exposing the workpiece to an etching process to remove thedielectric material from the barrier layer 114, without removing all ofthe first dielectric material 116 on the underlying layer 106. In oneembodiment, an etch process, developed by a person of ordinary skill inthe art of plasma etching, may be used to remove portions of the firstdielectric material 116 from the barrier layer 114. In anotherembodiment, the etch process may be used to remove the first dielectricmaterial 116 and the barrier layer 114 and expose the metal caps 112.However, before restarting the dielectric deposition process areplacement barrier layer may be selectively applied to the metal capsusing a barrier layer deposition process developed by a person ofordinary skill in the art of thin-film deposition.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer modules 310 a and 310 b may be used to transfer theworkpiece 100 to the etching module 330 such as first etching module 330a also hosted on the first common manufacturing platform 300, e.g.,transfer module 310 a removes the workpiece 100 from first film-formingmodule 320 a and transfers it to transfer module 310 b, which then maydeliver the workpiece 100 into the first etching module 330 a.Adjustments to the controlled environment may be made in transfermodules 310 a and 310 b if etching module 330 operates with differentparameters than first film-forming module 320 a, such as differentvacuum pressures.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 210, with reference to FIGS. 1E,2, and 3, the workpiece 100 is treated in an etching module 330 toremove the barrier layer 114 from the metal caps 112. The treatment ofthe workpiece 100 removes the barrier layer 114 from the metal caps 112,exposing the metal caps 112 at a bottom surface of the recessed pattern118 features, as shown in FIG. 1E. The treatment to remove the barrierlayer 114 may include an etch back treatment including etching thebarrier layer 114 off of the workpiece 100. The treatment to remove thebarrier layer 114 may occur in at least one of the etch modules 330.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer modules 310 a and 310 b may be used to transfer theworkpiece 100 to the film-forming module 320 such as first film-formingmodule 320 a also hosted on the first common manufacturing platform 300,e.g., transfer module 310 a removes the workpiece 100 from first etchingmodule 330 a and transfers it to transfer module 310 b, which then maydeliver the workpiece 100 into the first film-forming module 320 a or tosecond film-forming module 320 b. Adjustments to the controlledenvironment may be made in transfer modules 310 a and 310 b if thefilm-forming module 320 operates with different parameters than etchingmodule 330, such as different vacuum pressures.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 212, with reference to FIGS. 1F,2, and 3, an etch stop layer 120 is deposited over the recessed pattern118 features using one or more of the film-forming modules 320. The etchstop layer 120 may include nitrided films with metals, for exampletantalum nitride, or dielectric materials, for example silicon nitrides.The deposition of the etch stop layer 120 may be performed in the samefilm-forming module as in operation 204, operation 206, operation 208,or any combination thereof.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer modules 310 a and 310 b may be used to transfer theworkpiece 100 to the same or a different film-forming module 320 such asfirst film-forming module 320 a also hosted on the first commonmanufacturing platform 300, e.g., transfer module 310 a removes theworkpiece 100 from first film-forming module 320 a and transfers it totransfer module 310 b, which then may deliver the workpiece 100 into thefirst film-forming module 320 a or to second film-forming module 320 b.Adjustments to the controlled environment may be made in transfermodules 310 a and 310 b if, for example, the second film-forming module320 b operates with different parameters than, for example, the firstfilm module 320 a, such as different vacuum pressures.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 214, with reference to FIGS. 1G,2, and 3, a second dielectric layer of dielectric material is depositedover the etch stop layer 120 using one or more of the film-formingmodules 320, forming an interlayer dielectric film 122. The interlayerdielectric film 122 may include the same material as the firstdielectric layer 116, the underlying layer 106, or any combinationthereof. For example, the interlayer dielectric film 122 may include anoxide of silicon. The deposition of the interlayer dielectric film 122may be performed in the same film-forming module as in operation 204,operation 206, operation 208, operation 212, or any combination thereof.

Then, in operation 216, with reference to FIGS. 1H, 2, and 3, theworkpiece 100 is transferred to the ancillary module 350 for furtherprocessing. The ancillary module 350 does not operate in the controlledenvironment. The ancillary module 350 may include a track module 354 anda lithography module 352. The workpiece 100 is transferred from thefirst common manufacturing platform 300 to the ancillary module 350,leaving the controlled environment and breaking the vacuum of the firstcommon manufacturing platform 300. In some examples, the workpiece 100is transferred to the track module 354. A photo resist layer 140 is spunonto the upper surface of the workpiece 100, specifically the uppersurface of the interlayer dielectric 122, in the track module 354. Thephoto resist layer 140 is a light sensitive layer and is spun onto theupper surface of the workpiece 100 such that the photo resist layer 140is uniform and covers the upper surface of the workpiece 100, as shownin FIG. 1H.

Then, in operation 218, with further reference to FIGS. 1H, 2, and 3,the workpiece 100 is transferred to the lithography module 352. In someexamples, such as the ancillary module 350 shown in FIG. 3, thelithography module 352 may share a common module, such as the ancillarymodule 350, with the track module 354. Alternatively, the lithographymodule 352 may be a completely or partially separate module from thetrack module 354. In the lithography module 352, a mask (not shown)covers portions of the photo resist layer 140 such that portions notcovered by the mask are exposed. For example, as shown in FIG. 1H, theexposed portion 142 may be left exposed by the mask. The exposed portion142 of the photo resist layer 140 is subjected to light in thelithography module 352. The light weakens the photo resist layer 140that the light contacts, namely the exposed portion 142 of the photoresist layer 140. The mask covers the remainder of the photo resistlayer 140 and prevents portions other than the exposed portion 142 frombeing exposed to light in the lithography module 352. Thus, only theexposed portion 142 of the photo resist layer 140 is weakened byexposure to the light in the lithography module 352.

Then, in operation 226, with reference to FIGS. 1I, 2, and 3, theworkpiece 100 is developed in a baking process. The baking processremoves the exposed portion 142 from the workpiece 100. As shown in FIG.1I, the baking process results in the removal of the exposed portion 142(not shown in FIG. 1I because it was removed in the bake) and exposes aportion 144 of the upper surface of the interlayer dielectric 122.

Then, the workpiece 100 is transferred back to a controlled environment.This controlled environment may be present on a common manufacturingplatform. This common manufacturing platform may be the same ordifferent common manufacturing platform in which operations 202-214 wereperformed, that is the first common manufacturing platform 300.Alternatively, the workpiece 100 may be transferred to the second commonmanufacturing platform 360, which occurs here.

As shown in FIG. 3, the second common manufacturing platform 360includes afront end module (FEM) 362 and/or a transfer module 370 a thatmay be used to bring the workpiece 100 into the controlled environmentof the second common manufacturing platform 360, which controlledenvironment is maintained throughout at least a portion of the processflow 200. The controlled environment may include a vacuum environment,where at least some operations in the process flow 200 is conductedwithout breaking vacuum, or an inert gas atmosphere, or a combinationthereof. A single transfer module, such as transfer module 370 a, may becoupled between each processing module or tool, or separate transfermodules may be used for each tool transfer. Where different processingmodules on the second common manufacturing platform 360 requiredifferent controlled environments, such as different vacuum pressures orvacuum in one module followed by a module with inert gas atmosphere,multiple transfer modules may be used where the transfer modules assistin implementing the transitions between the different controlledenvironments. While a single transfer module may be useful in acluster-type tool where same-type processing modules are positioned in acircle around the transfer module, multiple transfer modules may be moreappropriate in an end-to-end platform configuration with differentprocessing module types.

A front-end module 362 may be used to load a cassette of workpieces (notshown), sequentially line up the workpieces and insert them into a loadlock, then into transfer module 370 a in a controlled environment, andthe transfer module 370 a sequentially loads the workpieces into aprocessing module. In the second common manufacturing platform 360 andwith respect to operation 222, the workpiece 100, which has beenreceived into the controlled environment, is loaded by the transfermodule 370 a into an etching module 390, such as first etching module390 b, hosted on the second common manufacturing platform 360 withoutleaving the controlled environment, e.g., without breaking vacuum.Etching modules 390 a, 390 b located on the second common manufacturingplatform 360 may be collectively referred to herein as etching modules390 where appropriate. Similarly, deposition modules 380 a, 380 b may becollectively referred to herein as deposition modules 380 whereappropriate. Adjustments to the controlled environment may be made intransfer module 370 a if etching module 390 operates with differentparameters than the front end module 362, such as different vacuumpressures.

Thereafter, and without leaving the controlled environment, e.g.,without breaking vacuum, in operation 222, with reference to FIGS. 1J,2, and 3, the exposed portion 144 of the interlayer dielectric film 122is etched to form one or more via features 124 a. The via features 124 aare formed by etching the interlayer dielectric film 122 to the etchstop layer 120 using one of the one or more etching modules 330. As aresult, the etch stop layer 120 is exposed at the bottom of the one ormore via features 124 a, as shown in FIG. 1J. Exposure of the etch stoplayer 120 may serve as an indication for the etching module 330 to stopetching deeper into the workpiece 100 toward the substrate 104.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer module 370 a may be used to transfer the workpiece 100to the etching module 390, such as second etching module 390 b, alsohosted on the second common manufacturing platform 360, e.g., transfermodule 370 a removes the workpiece 100 from etching module 390 a anddelivers the workpiece 100 into the second etching module 330 b.Adjustments to the controlled environment may be made in transfermodules 370 a if etching module 390 b operates with different parametersthan etching module 390 a, such as different vacuum pressures.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, with reference to FIGS. 1K, and 3, the photoresist layer 140 is etched from the upper surface of the interlayerdielectric 122, such as within second etching module 390 b. As a result,the upper surface of the interlayer dielectric 122 is exposed andprepared for deposition of metal feature material.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 224, with reference to FIGS. 1L,2, and 3, the exposed etch stop layer 120 is etched to further form oneor more via features 124 b. The via features 124 b are formed by etchingthe exposed etch stop layer 120 using one of the one or more etchingmodules 390. As a result, at least some of the metal caps 112 areexposed at the bottom of the one or more via features 124 b, as shown inFIG. 1L. Exposure of the metal caps 112 may serve as an indication forthe etching module 390 to stop etching deeper into the workpiece 100toward the substrate 104.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer module 370 a may be used to transfer the workpiece 100to the film-forming module 380 such as film-forming module 380 a or 380b also hosted on the second common manufacturing platform 360, e.g.,transfer module 370 a removes the workpiece 100 from etching module 390and delivers the workpiece 100 into the film-forming module 380 a or 380b. Adjustments to the controlled environment may be made in transfermodule 370 a if the film-forming module 380 operates with differentparameters than etching module 390, such as different vacuum pressures.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 226, with reference to FIGS. 1M,2, and 3, a metal 126 is deposited into the via features 124 b using thefilm-forming module 320. The via feature 124 b is filled with the metal126 over the metal caps 112 in the film-forming module 320. In someexamples, the metal 126 is selected from the group consisting ofruthenium, tungsten, cobalt, copper, and combinations thereof.

Optionally, the workpiece may be subjected to one or more cleaningprocesses before further patterning operations. For example, cleaningmay be performed in the same cleaning module 340 a, 340 b hosted on thefirst common manufacturing platform 300. A transfer module 310 may beused to transfer the workpiece from the film-forming module 380 to, forexample, the first common manufacturing platform 300, and then to thecleaning module 340. As shown, transfer modules 310 a, 310 b, 370 a maybe used to make the transfer, the transfer module 370 a removing theworkpiece from, for example, the film-forming module 380 a, andeventually transferring it to the transfer module 310 b, which thendelivers the workpiece into the cleaning module 340. Again, the firstcommon manufacturing platform 300 may include two identical cleaningmodules 340 on the same or opposing sides of the transfer module 310 b.It should be understood that second common manufacturing platform 360and/or ancillary module 350 also may include one or more cleaning moduleso that cleaning may be performed therein.

In one embodiment, and as will be discussed in more detail below, thefirst and/or second common manufacturing platform 300, 360advantageously includes an “active interdiction system.” As shown anddiscussed here with respect to the first common manufacturing platform300, the active interdiction system includes a workpiece measurementregion within a transfer module 310 hosted on the first commonmanufacturing platform 300 or an integrated metrology module (not shown)hosted on the first common manufacturing platform 300. The workpiecemeasurement region may be located in a dedicated area of the transfermodule 310, as described in more detail below. The workpiece measurementregion or metrology module may include an inspection system forgathering measurement data. As described in more detail below, theinspection system may include at least one optical source for directingan optical beam incident on a measurement surface of the workpiece andat least one detector arranged to receive an optical signal scatteredfrom the measurement surface of the workpiece. The active interdictionsystem may further include an intelligence system hosted on the firstcommon manufacturing platform 300 that is configured to gather data fromthe workpiece measurement region or metrology module and control theintegrated sequence of processing steps executed on the first commonmanufacturing platform 300, such as process flow 200.

For active interdiction in accordance with embodiments of the invention,the workpiece measurement region or metrology module collects real timedata “on the fly” pertaining to attributes of features or layers on thesemiconductor workpiece (e.g., film or feature thickness, feature depth,surface roughness, pattern shift, voids or other defects, loss ofselectivity, lateral overgrowth, uniformity, etc.) and uses such realtime data to concurrently control integration operating variables in theintegrated processing modules hosted on the first common manufacturingplatform 300. The data can be used in a feed-back and/or feed-forwardmanner to control operations performed on the workpiece in subsequentmodules and/or to control operations performed in prior modules on asubsequent workpiece, for example as will be explained below withreference to operations 250-272 of FIG. 2. In an embodiment, the firstcommon manufacturing platform 300 includes a correction module, whichmay be a film-forming module 320, an etching module 330, or other typeof treatment module as appropriate for applying corrective action orremedial treatment to the workpiece 100.

Unlike traditional metrology or process control, the workpiece does notleave the controlled environment of the first common manufacturingplatform 300 (for certain process steps) to enter a stand-alonemetrology tool thereby minimizing oxidation and defect generation, themeasurements are non-destructive such that no workpiece is sacrificed toobtain data thereby maximizing production output, and the data can becollected in real time as part of the process flow to avoid negativelyimpacting production time and to enable in-process adjustments to theworkpiece or to subsequent workpieces being sequentially processed onthe first common manufacturing platform 300. Additionally, themeasurements are not performed in the film-forming or etching modules,thereby avoiding issues when measurement devices are exposed to processfluids. For example, by incorporating workpiece measurement regions intothe transfer module, the data can be obtained as the workpiece istraveling between processing tools with little to no delay in theprocess flow, without exposure to process fluids, and without leavingthe controlled environment, e.g., without breaking vacuum. While the “onthe fly” data may not be as accurate as the data obtained fromtraditional destructive methods performed in stand-alone metrologytools, the nearly instantaneous feedback on the process flow and abilityto make real-time adjustment without interrupting the process flow orsacrificing yield is highly beneficial for high-volume manufacturing.

With further reference to the process flow 200 of FIG. 2, the method mayinclude inspecting the workpiece, such as performing metrology, i.e.,obtaining measurement data, using the active interdiction system at anyof various times throughout the integrated method, without leaving thecontrolled environment of the first common manufacturing platform 300,e.g., without breaking vacuum. Inspection of the workpiece may includecharacterizing one or more attributes of the workpiece and determiningwhether the attribute meets a target condition. For example, theinspection may include obtaining measurement data related to anattribute and determining whether a defectivity, a film conformality, athickness, a uniformity, and/or a selectivity condition meets a targetfor that condition. While the following discussion will focus onobtaining measurement data, it may be understood that other inspectiontechniques performed within the controlled environment of the commonmanufacturing platform are also within the scope of the invention.

The active interdiction system may include a single metrology module orworkpiece measurement region on the first common manufacturing platform300 or may include multiple metrology modules 312 c, 312 d or workpiecemeasurement regions 312 a, 312 b on the first common manufacturingplatform 300, as will be discussed in more detail below. Each metrologyoperation is optional, as indicated by the phantom lines in FIG. 2, butmay be advantageously performed at one or more points in the processflow to ensure the workpiece 100 is within specification to reducedefectivity and EPE. In one embodiment, measurement data is obtainedafter each step of the integrated sequence of processing steps conductedon the common manufacturing platform. The measurement data may be usedto repair the workpiece in a correction module prior to leaving thecommon manufacturing platform, and/or may be used to alter parameters ofthe integrated sequence of processing steps for subsequent workpieces.It should be understood that the ancillary module 350 and/or secondcommon manufacturing platform 360 can include a metrology module(s),e.g., metrology module 372 a, and advantageously include an “activeinterdiction system”, as discussed above and further explained belowwith respect to the first common manufacturing platform 300.

In broad terms, within the controlled environment of the first commonmanufacturing platform 300 and/or the second common manufacturingplatform 360 (and optionally the ancillary module 350), measurement datamay be obtained during the integrated sequence of processing stepsrelated to the formation of the fully self-aligned via and, based on themeasurement data, a determination may be made whether a thickness,width, or profile of any applied layer or metal cap meets a targetcondition. The applied layer or metal cap may include the underlyinglayer 106, the first dielectric layer 116, the second dielectric layer122, the etch stop layer 120, the barrier layer 114, the metal feature110, metal cap 112, photo resist layer 140, or combinations thereof.When the thickness, width, or profile of any applied layer or metal capis determined to not meet the target condition, the workpiece 100 may beprocessed in a correction module on the common manufacturing platform toalter the sidewall spacer pattern. In one embodiment, when the targetthickness, width, or profile of the sidewall spacer pattern is not met,the sidewall spacer pattern may be repaired by (i) obtaining measurementdata related to the metal caps and/or of the exposed surfaces of theunderlying layer 106, first dielectric layer 116, or second dielectriclayer 122 for use in a first verification process to verify that themetal caps completely cover the exposed surfaces 108 of the metalfeatures 110 and/or to verify an absence of metal nuclei on the exposedsurfaces 108 of the underlying layer 106 as a contaminant; (ii)obtaining measurement data related to attributes of the metal caps 112for use in a second verification process to verify that the barrierlayer 114 is removed; (iii) obtaining measurement data related toattributes of the first dielectric layer 116 material selectivelydeposited on the exposed surfaces of the underlying layer 106 for use ina third verification process to verify that the first dielectric layer116 material completely covers the exposed surfaces of the underlyinglayer 106 and/or to verify an absence of the first dielectric layer 116material on the exposed surfaces 108 of the metal caps 112, and (iv)obtaining measurement data related to attributes of the metal caps 112exposed at the bottom of the one or more via features 124 a, 124 b foruse in a fourth verification process to verify that the exposed etchstop layer 120 is removed.

In an embodiment, when a conformality or uniformity of an underlyinglayer 106, dielectric layer 116, interlayer dielectric film 122, metalcap 112, barrier layer 114, or etch stop layer 120 applied in afilm-forming module 320 on the first common manufacturing platform 300does not meet a target conformality or target uniformity for the layeror metal cap, corrective action may be taken to repair the layer ormetal cap. Repairing a selective layer or metal cap may be accomplishedby removing the applied layer or metal cap and reapplying the layer ormetal cap, selectively applying an additional layer or metal cap,etching the applied layer or metal cap, or a combination of two or morethereof. For example, the workpiece 100 may be transferred to acorrection etching module 330 to remove the layer or metal cap orpartially etch the layer or metal cap, and/or the workpiece 100 may betransferred to a correction film-forming module 320 to reapply the layeror metal cap after it is removed or to apply additional dielectric ormetal material over the existing layer or metal cap or partially etchedlayer or metal cap.

The process flow 200 of FIG. 2 will now be described in detail with theoptional metrology operations. Operation 202 includes receiving theworkpiece into the first common manufacturing platform 300, theworkpiece having a pattern of metal features in a dielectric layerwherein exposed surfaces of the metal features and exposed surfaces ofthe dielectric layer together define an upper planar surface. Operation250 includes optionally performing metrology to obtain measurement datarelated to attributes of the incoming workpiece, such as attributes ofthe metal features, layout of the metal feature pattern, and underlyinglayer within which metal features are formed, which measurement data maybe used to adjust and/or control process parameters of any one ofoperations 202-226. Additionally, one or more of the operations 202-226may be performed without performed entirely, or in part, on the commonmanufacturing platforms 330, such that the end-to-end sequencingdescribed in operations 202-226 may be performed, in part, on aplurality of processing tools.

Operation 204 includes selectively depositing metal caps on the exposedsurfaces of the metal features relative to the exposed dielectricmaterial using one of the one or more of the film-forming modules.Operation 252 includes optionally performing metrology to obtainmeasurement data related to attributes of the workpiece having theselective metal caps applied, such as attributes of the selective metalcaps, the metal features as affected by the metal cap deposition, and/orthe underlying layer into which the metal features are formed asaffected by the metal cap deposition, which measurement data may be usedto adjust and/or control process parameters of any one of operations206-226, may be used to make adjustments for subsequent workpieces tothe incoming attributes of the workpieces in operation 202 or tooperation 204, or may be used to repair the workpiece before continuedprocessing. In one embodiment, when the measurement data indicates thatone or more attributes do not meet a target condition, the workpiece maybe transferred to a correction module to repair the selectively appliedmetal caps. For example, when a selectivity or uniformity of the metalcaps do not meet a target selectivity or target uniformity, correctiveaction may be taken in one or more correction modules, such as removingthe metal caps and reapplying the metal caps, selectively applyingadditional metal cap material, etching the metal cap, or a combinationof two or more thereof.

Operation 206 includes selectively forming a barrier layer on the metalcaps, using one of the one or more film-forming modules, relative to theexposed dielectric material. Operation 254 includes optionallyperforming metrology to obtain measurement data related to attributes ofthe workpiece having the barrier layer deposited thereon, such asattributes of the barrier layer, metal caps as affected by the barrierlayer, the metal features as affected by the barrier layer, and/or theunderlying layer as affected by the barrier layer, which measurementdata may be used to adjust and/or control process parameters of any oneof operations 208-226, may be used to make adjustments for subsequentworkpieces to the incoming attributes of the workpieces in operation 202or to operations 204-206, or may be used to repair the workpiece beforecontinued processing. In one embodiment, when the measurement dataindicates that one or more attributes do not meet a target condition,the workpiece may be transferred to a correction module to repair thebarrier layer. For example, when the thickness, width, or profile of thebarrier layer does not meet a target thickness, width, or profile of themetal caps, corrective action may be taken in one or more correctionmodules, such as by selectively depositing additional barrier layermaterial onto the metal caps, reshaping the barrier layer, etching thebarrier layer, or a combination of two or more thereof. In someexamples, the remedial action to ameliorate the non-conformity when themeasurement data indicates the non-conformity is present on theworkpiece includes removing the self-assembled monolayer when thepre-determined monolayer coverage threshold is exceeded and/or removingmetal nuclei from the dielectric layer when the predetermined metalnuclei threshold is exceeded.

Operation 208 includes selectively depositing a first dielectricmaterial on the exposed surfaces of the dielectric layer using one ofthe one or more film-forming modules to form a recess pattern in thefirst dielectric material, the selective deposition being based, atleast in part, on a deposition rate of the first dielectric materialbeing higher on the exposed surfaces than on the metal caps, the recesspattern comprising a sidewall including a portion of the firstdielectric material. Operation 256 includes optionally performingmetrology to obtain measurement data related to attributes of theworkpiece having the recess pattern in the first dielectric layer, suchas attributes of the sidewalls, the depth of the recessed feature in thefirst dielectric layer, the exposure of the barrier layer, and thecoverage of the underlying dielectric layer on the workpiece as affectedby the deposition of the first dielectric layer and/or the underlyinglayer as affected by the deposition of the first dielectric layer, whichmeasurement data may be used to adjust and/or control process parametersof any one of operations 210-226, may be used to make adjustments forsubsequent workpieces to the incoming attributes of the workpieces inoperation 202 or to operations 204-208, or may be used to repair theworkpiece before continued processing. In one embodiment, when themeasurement data indicates that one or more attributes do not meet atarget condition, the workpiece may be transferred to a correctionmodule to repair the first dielectric layer. For example, when thethickness, width, or profile of the first dielectric layer does not meeta target thickness, width, or profile of the first dielectric layer,corrective action may be taken in one or more correction modules, suchas by selectively depositing additional material onto the underlyinglayer, etching the first dielectric layer, or a combination of two ormore thereof. The remedial action may include removing theself-assembled monolayer from the metals caps based, at least in part,on the measurement data related to attributes of the metal caps and/orremoving the first dielectric layer from the exposed surfaces of themetal caps based, at least in part, on measurement data related toattributes of the first dielectric material.

Operation 210 includes treating the workpiece to expose the metal capsat the bottom surfaces of the recess pattern. Operation 258 includesoptionally performing metrology to obtain measurement data related toattributes of the workpiece treated to have the metal caps exposed atthe bottom surface of the recess pattern, such as attributes of themetal caps, the barrier layer as affected by the treatment, and/or theunderlying layer as affected by the treatment, which measurement datamay be used to adjust and/or control process parameters of any one ofoperations 212-226, may be used to make adjustments for subsequentworkpieces to the incoming attributes of the workpieces in operation 202or to operations 204-208, or may be used to repair the workpiece beforecontinued processing. In one embodiment, when the measurement dataindicates that one or more attributes do not meet a target condition,the workpiece may be transferred to a correction module to repair thetreatment of the workpiece to expose the metal caps at the bottomsurfaces of the recess pattern. For example, when a conformality oruniformity of the recess pattern does not meet a target conformality ortarget uniformity for the recess pattern, corrective action may be takenin one or more correction modules, such as further treatment of therecess pattern to further remove the barrier layer.

Operation 212 depositing an etch stop layer over the recess patternusing one of the one or more film-forming modules. Operation 260includes optionally performing metrology to obtain measurement datarelated to attributes of the workpiece having the etch stop layer formedthereon, such as attributes of the workpiece having the etch stop layerformed thereon, the recess pattern as affected by the etch stop layer,and/or the underlying layer as affected by the etch stop layer, whichmeasurement data may be used to adjust and/or control process parametersof any one of operations 214-226, may be used to make adjustments forsubsequent workpieces to the incoming attributes of the workpieces inoperation 202 or to operations 204-210, or may be used to repair theworkpiece before continued processing. In one embodiment, when themeasurement data indicates that one or more attributes do not meet atarget condition, the workpiece may be transferred to a correctionmodule to repair the etch stop layer over the recess pattern. Forexample, when the thickness, width, or profile of the etch stop layerdoes not meet a target thickness, width, or profile of the etch stoplayer, corrective action may be taken in one or more correction modules,such as by selectively depositing additional material onto the recesspattern, reshaping the etch stop layer, etching a portion of the etchstop layer, or a combination of two or more thereof.

Operation 214 includes depositing a second dielectric material on theetch stop layer to form an interlayer dielectric film over and/or in therecess pattern using one of the one or more film-forming modulesOperation 262 includes optionally performing metrology to obtainmeasurement data related to attributes of the workpiece having thesecond dielectric material, such as attributes of the etch stop layer asaffected by the second dielectric material and/or the underlying layeras affected by the second dielectric material, which measurement datamay be used to adjust and/or control process parameters of operation214, may be used to make adjustments for subsequent workpieces to theincoming attributes of the workpieces in operation 202 or to operations204-226, or may be used to repair the workpiece before continuedprocessing. In one embodiment, when the measurement data indicates thatone or more attributes do not meet a target condition, the workpiece maybe transferred to a correction module to repair the interlayerdielectric film. For example, when the thickness, width, or profile ofthe interlayer dielectric film does not meet a target thickness, width,or profile of the interlayer dielectric film, corrective action may betaken in one or more correction modules, such as by selectivelydepositing additional second dielectric material onto the etch stoplayer, etching the second dielectric material, or a combination of twoor more thereof.

Hereinafter, measurement data may continue to be obtained during thesequence of processing steps related to the formation of the fullyself-aligned via. But here, if measurement data is going to be obtainedutilizing the first common manufacturing platform 300, workpieces willneed to be transferred between platforms 300, 360 and/or ancillarymodule 350. In certain embodiments, it is contemplated that the secondcommon manufacturing platform 360 and/or ancillary module 350 caninclude their own metrology module(s), e.g., metrology module 372 a, andadvantageously include their own “active interdiction system”. In thatinstance, measurement data may continue to be obtained within acontrolled environment at least with respect to the second commonmanufacturing platform 360 and as associated with its own correspondingsequence of processing steps, for example.

Operation 216 includes depositing a photo resist layer on the interlayerdielectric film. Operation 264 includes optionally performing metrologyto obtain measurement data related to attributes of the workpiece havingthe photo resist layer deposited thereon, such as attributes of the etchstop layer as affected by the photo resist layer and/or the underlyinglayer as affected by the photo resist layer, which measurement data maybe used to adjust and/or control process parameters of operations 226,may be used to make adjustments for subsequent workpieces to theincoming attributes of the workpieces in operation 202 or to operations204-226, or may be used to repair the workpiece before continuedprocessing. In one embodiment, when the measurement data indicates thatone or more attributes do not meet a target condition, the workpiece maybe transferred to a correction module to repair the photo resist layer.For example, when the thickness, width, uniformity, or profile of thephoto resist layer does not meet a target thickness, width, uniformity,or profile of the interlayer dielectric film, corrective action may betaken in one or more correction modules, such as by selectivelydepositing additional photo resist layer material onto the workpiece,etching the photo resist layer, or a combination of two or more thereof.

Operation 218 includes exposing a photo resist layer to light at leastto weaken the photo resist layer. Operation 266 includes optionallyperforming metrology to obtain measurement data related to attributes ofthe workpiece having the photo resist layer deposited thereon, such asattributes of portions of the photo resist layer as affected by thelight exposure. This measurement data may be used to adjust and/orcontrol process parameters of operations 226, may be used to makeadjustments for subsequent workpieces to the incoming attributes of theworkpieces in operation 202 or to operations 204-226, or may be used torepair the workpiece before continued processing. In one embodiment,when the measurement data indicates that one or more attributes do notmeet a target condition, the workpiece may be transferred to acorrection module to repair the photo resist layer. For example, whenthe specific portions or desired weakness of the photo resist layer doesnot meet a target specific portions or desired weakness of the photoresist layer, corrective action may be taken in one or more correctionmodules, such as by selectively depositing additional photo resist layermaterial onto the workpiece, etching the photo resist layer, furtherexposing portions of the photo resist layer to light, or a combinationof two or more thereof.

Operation 226 includes baking or developing a portion of the photoresist layer on the interlayer dielectric film. Operation 268 includesoptionally performing metrology to obtain measurement data related toattributes of the workpiece having the photo resist layer depositedthereon, such as attributes of the photo resist layer and/or attributesof the interlayer dielectric film as affected by the photo resist layer,which measurement data may be used to adjust and/or control processparameters of operations 226, may be used to make adjustments forsubsequent workpieces to the incoming attributes of the workpieces inoperation 202 or to operations 204-226, or may be used to repair theworkpiece before continued processing. In one embodiment, when themeasurement data indicates that one or more attributes do not meet atarget condition, the workpiece may be transferred to a correctionmodule to repair the photo resist layer. For example, when the portionsof the photo resist layer removed in the baking/development process donot meet a target portion removed, corrective action may be taken in oneor more correction modules, such as by selectively depositing additionalphoto resist layer material onto the workpiece, etching the photo resistlayer, further exposing portions of the photo resist layer to light, ora combination of two or more thereof.

Operation 222 includes etching one or more via features through theinterlayer dielectric to the etch stop layer using one of the one ormore etching modules, the etch stop layer exposed at a bottom of the oneor more via features. Operation 270 includes optionally performingmetrology to obtain measurement data related to attributes of theworkpiece having the etched via features though the interlayerdielectric film, such as attributes of the etch stop layer as affectedby the second dielectric material and/or the underlying layer asaffected by the second dielectric material, which measurement data maybe used to adjust and/or control process parameters of operation 222,may be used to make adjustments for subsequent workpieces to theincoming attributes of the workpieces in operation 202 or to operations204-226, or may be used to repair the workpiece before continuedprocessing. In one embodiment, when the measurement data indicates thatone or more attributes do not meet a target condition, the workpiece maybe transferred to a correction module to repair the interlayerdielectric film. For example, when the thickness, width, or profile ofthe interlayer dielectric film does not meet a target thickness, width,or profile of the interlayer dielectric film, corrective action may betaken in one or more correction modules, such as by selectivelydepositing additional second dielectric material onto the etch stoplayer, etching the second dielectric material, or a combination of twoor more thereof.

Operation 224 includes etching the exposed etch stop layer at the bottomof the one or more via features using one of the one or more etchingmodules to expose the metal caps at the bottom of the one or more viafeatures. Operation 272 includes optionally performing metrology toobtain measurement data related to attributes of the workpiece havingthe etched via features though the etch stop layer, such as attributesof the etch stop layer as affected by the exposure of the metal capand/or the underlying layer as affected by the exposure of the metalcap, which measurement data may be used to adjust and/or control processparameters of operation 224, may be used to make adjustments forsubsequent workpieces to the incoming attributes of the workpieces inoperation 202 or to operations 204-226, or may be used to repair theworkpiece before continued processing. In one embodiment, when themeasurement data indicates that one or more attributes do not meet atarget condition, the workpiece may be transferred to a correctionmodule to repair the via feature through the etch stop layer. Forexample, when the thickness, width, or profile of the via featurethrough the etch stop layer does not meet a target depth, width, orprofile of the via feature, corrective action may be taken in one ormore correction modules, such as by etching the etch stop layer.

Operation 226 includes filling the one or more via features over themetal caps with a metal using one of the one or more film-formingmodules. Operation 226 may further include optionally performingmetrology to obtain measurement data related to attributes of theworkpiece having via feature filled over the metal caps, such asattributes of the via feature as affected by filling the one or more viafeatures over the metal caps and/or the underlying layer as affected byfilling the one or more via features over the metal caps, whichmeasurement data may be used to adjust and/or control process parametersof operation 226, may be used to make adjustments for subsequentworkpieces to the incoming attributes of the workpieces in operation 202or to operations 204-226, or may be used to repair the workpiece beforecontinued processing. In one embodiment, when the measurement dataindicates that one or more attributes do not meet a target condition,the workpiece may be transferred to a correction module to repair thefilling of the via feature. For example, when the thickness, width, orprofile of the filled via feature does not meet a target depth, width,or profile of the via feature, corrective action may be taken in one ormore correction modules, such as by depositing additional metal into thevia feature, etching an overburdened filled via feature, or acombination of two or more thereof.

Process parameters, as referred to above, may include any operatingvariable within a processing module, such as but not limited to: gasflow rates; compositions of etchants, deposition reactants, purge gases,etc.; chamber pressure; temperature; electrode spacing; power; etc. Theintelligence system of the active interdiction system is configured togather measurement data from the inspection system and control theintegrated sequence of processing steps executed on the commonmanufacturing platform, for example, by making in situ adjustments toprocessing parameters in subsequent processing modules for the workpiecein process, or by changing process parameters in one or more processingmodules for subsequent workpieces. Thus, the obtained measurement datamay be used to identify a needed repair to the workpiece during theintegrated sequence of processing steps to avoid having to scrap theworkpiece, and/or to adjust processing parameters for the integratedsequence of processing steps for steps performed on the same workpieceafter the measurement data is obtained or for processing subsequentworkpieces to reduce occurrences of the target conditions not being metfor the subsequent workpieces.

Referring now to FIGS. 4A-4B, a comparison of traditional via to FSAVfabrication is shown. For example, workpiece 100 is the same workpieceas was described above and shown in FIG. 1M. As shown in FIG. 4A,workpiece 100 is an example of a workpiece 100 having a fullyself-aligned via including the substrate 104, underlying layer 106,metal features 110, metal caps 112, first dielectric layer 116, etchstop layer 120, second dielectric layer 122, and filled feature withmetal 126. Referring to FIG. 4B, workpiece 100′ is an example of atraditionally fabricated filled recessed feature on a workpiece 100′including an underlying layer 106′, a metal cap 112′, a metal feature110′, and a filled feature with metal 126′. A via distance V from thecorner of the metal cap 112 to the corner of the metal 126 is largerthan a via distance V′ from the metal cap 112′ to the metal 126′. TheFSAV arrangement is advantageous over the conventional arrangement atleast because under the conventional arrangement, the semiconductor mayshort, causing damage to the semiconductor or even failure.Semiconductors including fully self-aligned vias short far less thantraditional arrangements leading to a more reliable product.

As disclosed herein the term “metrology module” or “measurement module”refers to a module/system/sensor/tool that can make measurements on aworkpiece to detect or determine various non-conformities or variationson the workpiece, such as parametric variations, or to detect ordetermine defects on the workpiece, such as a contamination of somekind. As used herein, the term “inspection system” will generally referto the tool or system of a measurement process or module that measuresand collects data or signals associated with the measurement. Themeasurement modules will make measurements and provide data for use inthe processing platform as disclosed further herein. The terms“metrology module” and “measurement module” will be used interchangeablyherein, and generally refer to measurement or metrology or sensing toolsused to detect and measure attributes of a workpiece that are indicativeof the processing of the workpiece and the layers and devices beingformed thereon.

To move workpieces between the various processing modules, the commonmanufacturing platform, such as the first and/or second commonmanufacturing platform 300, 360, and ancillary module 350 can generallyincorporate one or more workpiece transfer modules that are hosted onthe common manufacturing platform and are configured for the movement ofthe workpiece between the processing modules and the measurementmodule(s). A measurement module might be coupled with the workpiecetransfer module similar to a processing module. In some embodiments ofthe invention, as disclosed herein, a measurement module or theinspection system associated therewith is incorporated with or inside atransfer module to provide for measurement or metrology as the workpieceis moved between processing modules. For example, a measurement module,or a portion thereof, might be positioned inside an internal space ofthe transfer module. Herein, the combination transfer and measurementapparatus will be referred to as a transfer measurement module (“TMM”).

In one embodiment, the common manufacturing platform including bothprocessing chambers and measurement modules, such as the first and/orsecond common manufacturing platform 300, 360, and the ancillary module350 can be actively controlled by a system that processes the measureddata associated with an attribute on the workpiece and uses the measureddata for controlling movement and processing of the workpiece in aprocessing sequence. In accordance with embodiments of the invention,the control system uses measured data and other data to performcorrective processing based in part on the measured data to provideactive interdiction of the processing sequence to correctnon-conformities or defects. More specifically, an active interdictioncontrol system can be hosted on the common manufacturing platforms andancillary module 350 and configured to perform corrective processingbased in part on the measured data, wherein the corrective processing ofthe workpiece might be performed in the processing modules of theplatform that are upstream or downstream in the process sequence toaddress situations where non-conformities or defects are detected. In anembodiment of the invention, the workpiece is maintained in one or morecontrolled environments, such as under vacuum, for example. That is, onthe common manufacturing platform, the processing modules and themeasurement module can operate in a controlled environment, and theworkpiece transfer module transfers the workpiece between the pluralityof processing modules in the processing sequence and one or moremeasurement modules without leaving the controlled environment.

As used herein, the term “active interdiction” refers generally to thecontrol system as implemented for capturing measurement/metrology datain real time with respect to various fabrication processes to obtaindata on workpiece attributes and thereby detect non-conformities ordefects and the corrective aspects of the control to correct orameliorate the non-conformities or defects. The active interdictioncontrol system uses the data for correction and amelioration of variousnon-conformities in the semiconductor fabrication process by activelyvarying the processing sequence and/or the operation of modules thatperform process steps. Thus, the active interdiction control system alsointerfaces with one or more transfer modules (e.g., 310) used to moveworkpieces through the process. The active interdiction control system(322 in FIG. 3, as further described below) coordinates the datacollection and data analysis and detection of non-conformities with thefabrication process and further directs the actions of multipleprocessing modules so as to address the non-conformities or defects thatare detected. The active interdiction control system is implementedgenerally by one or more computer or computing devices as describedherein that operate a specially designed sets of programs such as deeplearning programs or autonomous learning components referred tocollectively herein as active interdiction components. As may beappreciated, the active interdiction control system may incorporatemultiple programs/components to coordinate the data collection fromvarious measurement modules and the subsequent analysis. The activeinterdiction control system interfaces with the multiple processingmodules in the common manufacturing platform in order to address variousmeasured non-conformities/defects to correct or ameliorate thenon-conformities/defects. The active interdiction control system willthereby control one or more of the processing modules and the processingsequence to achieve the desired results of the invention, which may bereferred to as the target conditions or predetermined thresholds.

The active interdiction control system also can control the transfermodules in order to move the workpieces to upstream and/or downstreamprocessing modules when non-conformities/defects are detected. That is,depending upon what is detected, the system of the invention may movethe workpiece further along in the processing sequence, or may directthe workpiece to a correction module or to an upstream processing moduleto correct or otherwise address a detected non-conformity or defect. Assuch, feedforward and feedback mechanisms are provided through thetransfer modules to provide the active interdiction of the invention.Furthermore, the processing sequence might be affected upstream ordownstream for future workpieces.

The active interdiction features of the invention improve performance,yield, throughput, and flexibility of the manufacturing process usingrun-to-run, wafer-to-wafer, within the wafer and real-time processcontrol using collected measurement/metrology data. The measured data iscollected, in real time during the processing, without removing theworkpiece/substrate/wafer from the controlled processing environment. Inaccordance with one feature of the invention, in a common manufacturingplatform, for example, the measurement data may be captured while thesubstrate remains in a controlled environment, such as under vacuum, forexample. That is, the workpiece transfer module(s) can be configured fortransferring the workpiece between the plurality of processing modulesand the measurement modules without leaving the controlled environment.The active interdiction control can provide a multivariate, model-basedsystem that is developed in conjunction with feed-forward and feedbackmechanisms to automatically determine the optimal recipe for eachworkpiece based on both incoming workpieces and module or tool stateproperties. The active interdiction control system uses fabricationmeasurement data, process models and sophisticated control algorithms toprovide dynamic fine-tuning of intermediate process targets that enhancefinal device targets. The interdiction system enables scalable controlsolutions across a single chamber, a process tool, multi-tools, aprocess module and multi-process modules on a common manufacturingplatform using similar building blocks, concepts, and algorithms asdescribed herein.

Referring again to FIG. 3, FIG. 3 is a schematic diagram of anothersystem for implementing an embodiment of the present invention on firstcommon manufacturing platform 300. The platform 300 incorporates aplurality of processing modules/systems for performing integratedworkpiece processing and workpiece measurement/metrology under thecontrol of an active interdiction control system 322 according toembodiments of the invention. FIG. 3 illustrates an embodiment of theinvention wherein one or more workpiece measurement modules are coupledtogether with one or more workpiece processing modules through one ormore transfer modules. In that way, in accordance with features of theinvention, an inspection of the workpiece may be made to provide themeasurement data associated with an attribute of the workpiece, such asregarding material properties of the workpiece and the various thinfilms, layers and features that are formed on the workpiece while theworkpiece remains within the common manufacturing platform. As discussedherein, measurements and analysis may be made immediately uponcompletion of processing steps, such as an etch or deposition step, andthe measurement data gathered may be analyzed and then used within thecommon manufacturing platform to address any measurements or featuresthat are out of specification or non-conformal or represent a defectwith respect to the workpiece design parameters. The workpiece does notneed to be removed from the common manufacturing platform to takecorrective action, but rather, can remain under the controlledenvironment.

Referring to FIG. 3, common manufacturing platform 300 isdiagrammatically illustrated. Platform 300 includes the front-end module302 for introducing one or more workpieces into the manufacturingplatform. As is known, the front-end module (FEM) may incorporate one ormore cassettes holding the workpieces. The front-end module may bemaintained at atmospheric pressure but purged with an inert gas toprovide a clean environment. One or more workpieces may then betransferred into a transfer module 310, such as through one or moreload-lock chambers (not shown) as discussed herein. The transfer modulesof FIG. 3 are transfer measurement modules (TMM) that includemeasurement tools or inspection systems integrated therein for capturingdata from a workpiece. Multiple TMM's 310 may be interfaced forproviding movement of a workpiece through a desired sequence. Thetransfer measurement modules 310 are coupled with a plurality ofprocessing modules. Such processing modules may provide variousdifferent processing steps or functions and may include one or more etchmodules 330, one or more film-forming modules 320, one or more cleaningmodules 340, and one or more measurement modules 312 a, 312 b, 312 c,312 d. In accordance with embodiments of the invention as disclosedfurther herein, measurement modules may be accessed through the transfermodules 310 before or after each processing step. In one embodiment, themeasurement modules, such as 312 c, 312 d, are located outside of thetransfer modules 310 and are accessed to insert and receive workpiecessimilar to the various processing modules and may be referred to hereinas metrology modules that reside within the controlled environment ofthe first common manufacturing platform 300. Alternatively, measurementmodules or at least a portion thereof, such as modules 312 a, 312 b, maybe located in a respective transfer module. More specifically, all or aportion of a measurement module 312 a, 312 b is located in a transfermodule 310 to define a measurement region therein where a workpiecemight be positioned for measurement during a transfer process. Themeasurement region is located in a dedicated area of the transfer module310 and is accessible by the transfer mechanism of the transfer modulefor positioning the workpiece. As noted, this makes the transfer moduleessentially a transfer measurement module (TMM) as discussed herein.

Generally, the transfer module defines a chamber therein that houses atransfer robot that is capable of moving workpieces, under vacuum,through various gate valves and access or transfer ports into variousprocessing modules or measurement modules. By maintaining themeasurement modules on the first common manufacturing platform 300, theyare readily accessed, such as between one or more of the processingsteps to provide the necessary measured analytical data on-the-fly thatwill be used to address any workpiece out of specification or otherwisenon-conformal with the workpiece design plans for a particular workpieceor to address detectable defects. In that way, real time data isprovided to allow a fabricator to recognize problems early in the systemso that remedial action may be taken in the current processing sequence,such as in a following processing step, in a previous processing step,and/or in a future processing step depending upon the captured data andthe detected non-conformities or defects. In that way, productivity andefficiency may be increased, process monitoring overhead may be reduced,and wasted product, in the form of rejected or ejected workpieces may bereduced. This all provides a significant cost savings to a fabricator ordevice maker.

As noted, in one embodiment of the invention that incorporates theactive interdiction control system 322, one or more measurement modulesare hosted on a common manufacturing platform with processing modulesfor providing measured data regarding an attribute of the workpiece. Thedata is used by the active interdiction control system 322 for detectingnon-conformities and for performing corrective processing of theworkpiece when non-conformities are detected. The corrective processingis performed upstream and/or downstream in the process sequence whennon-conformities are detected. Again, as indicated above, it isunderstood that the second common manufacturing platform 360 and/orancillary module 350 can include a metrology module(s), such asmetrology module 372 a, and advantageously include an “activeinterdiction system” like the first common manufacturing platform 300,as discussed in detail above.

FIGS. 5A-5K illustrate schematic cross-sectional diagrams illustratingan embodiment of a fully self-aligned via formation method for aworkpiece 500. FIG. 6 is a flow chart of a process flow 600corresponding to the method of FIGS. 5A-5K. As explained above, FIG. 3illustrates an embodiment of an arrangement of a first commonmanufacturing platform 300 together with an ancillary module 350 and asecond common manufacturing platform 360 that may be used for performingprocess flow 200. The embodiment of FIG. 3 similarly may be used forperforming process flow 600. To that end, the process flow 600 of FIG. 6and the common manufacturing platforms 300, 360, and the ancillarymodule 350 will be referenced throughout the following sequentialdiscussion of FIGS. 5A-5K in which workpiece 500 is described as itproceeds through a sequence of processing steps.

In operation 602 of process flow 600 and as shown in FIG. 5A, aworkpiece 500 having a pattern of metal features 510 in an underlyinglayer 506 is provided into the first common manufacturing platform 300.The workpiece 500 includes the pattern of metal features 510 and theunderlying layer 506 positioned on the substrate 504. To those familiarin the current art, different schemes are known for creating a patternof metal features 510 on a substrate. For simplicity, workpiece 500 isdepicted with a substrate 504 having an underlying layer 506 thereon,although it may be understood that the structure on which the metalfeatures 510 are formed may be a multi-layer structure of which theunderlying layer 506 is just one of multiple layers.

The underlying layer 506 may be an oxide layer including silicon oxide,silicon dioxide, a carbon doped silicon oxide, a porous carbon dopedsilicon oxide, or some other oxide of silicon. In the case of a porousoxide, a pore sealing process may be performed prior to operation 604(not shown). Alternatively or in addition, the underlying layer 506 maybe a dielectric layer.

The metal features 510 may include, but is not limited to copper,ruthenium, cobalt, tungsten, or combinations thereof. Additionally, aliner layer 511 is included in the recessed feature along with the metalmaterial in the metal features 510. The liner layer 511 may includetantalum nitride, and inhibits the metal from contacting the oxideand/or dielectric material in the underlying layer 506. The liner layer511 may serve to bond the metal material in the metal feature 510 to theunderlying layer 506. Alternatively or in addition, the liner layer 511may serve to prevent the metal material in the metal feature 510 fromdiffusing into the underlying layer 506.

As shown in FIG. 3, a front end module (FEM) 302 or a transfer module310 a may be used to bring the workpiece into the controlled environmentof the first common manufacturing platform 300, which controlledenvironment is maintained throughout at least a portion of the processflow 600. The controlled environment may include a vacuum environment,where at least some operations in the process flow 600 are conducted insequence without breaking vacuum, or an inert gas atmosphere, or acombination thereof. A single transfer module may be coupled betweeneach processing module or tool, such as each of transfer modules 310 a,310 b shown in FIG. 3, or separate transfer modules may be used for eachtool transfer. Transfer modules 310 a-b may be collectively referred toherein as transfer modules 310 where appropriate. Where differentprocessing modules on the first common manufacturing platform 300require different controlled environments, such as different vacuumpressures or vacuum in one module followed by a module with inert gasatmosphere, multiple transfer modules 310 may be used where the transfermodules 310 assist in implementing the transitions between the differentcontrolled environments. While a single transfer module may be useful ina cluster-type tool where same-type processing modules are positioned ina circle around the transfer module, multiple transfer modules 310 maybe more appropriate in an end-to-end platform configuration withdifferent processing module types such as that depicted in FIG. 3.However, the embodiments herein do not preclude an end-to-end platformconfiguration that utilizes a single transfer module that is coupled toeach of the processing modules, or some configuration in between, forexample, a common transfer module for adjacent same-type processingmodules that are used in sequence.

A front-end module 302 may be used to load a cassette of workpieces (notshown), sequentially line up the workpieces and insert them into a loadlock, then into a transfer module 310 a in a controlled environment, andthe transfer module 310 a sequentially loads the workpieces into aprocessing module. In the first common manufacturing platform 300, inoperation 602, the workpiece 100, which has been received into thecontrolled environment, is loaded by the transfer module 310 a into afilm-forming module 320 a or 320 b hosted on the first commonmanufacturing platform 300. Film-forming modules 320 a, 320 b may becollectively referred to herein as film-forming modules 320 whereappropriate. Similarly, etching modules 330 a, 330 b may be collectivelyreferred to herein as etching modules 330 where appropriate. Similarly,metrology modules 312 a-d may be collectively referred to herein asmetrology modules 312 where appropriate. Similarly, cleaning modules 340a, 340 b may be collectively referred to herein as cleaning modules 340where appropriate.

Referring to FIGS. 5B, 6, and 3, in operation 604, in the etching module330, the metal features 510 are etched such that the exposed surface 508is lowered or recedes into the workpiece 500. The thus-lowered exposedsurfaces 508 of the metal features 510 form a recess pattern on theworkpiece 500 together with the liner layer 511.

Then, without leaving the controlled environment, e.g., without breakingvacuum, the workpiece 500 may stay in the same etching module 330 or betransferred using transfer modules 310 to a different etching module330, such as etching module 330 b. Adjustments to the controlledenvironment may be made in transfer modules 310 a and 310 b if theetching module 330 for a subsequent operation operates with differentparameters than the etching module from used in a current or previousoperation, such as different vacuum pressures.

Referring to FIGS. 5C, 6, and 3, in operation 606, in the etching module330, the liner layers 511 are etched to lower the liner layers 511 intothe workpiece 500. The liner layers 511 are lowered such that the upperedge of the liner layers 511 is coplanar with the exposed surface 508 orthe lowered metal features 510. The thus-lowered liner layers 511 andmetal features 510 form a recess pattern on the workpiece 500.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer modules 310 a and 310 b may be used to transfer theworkpiece 100 to the film-forming module 520 such as film-forming module520 a also hosted on the first common manufacturing platform 300, e.g.,transfer module 310 a removes the workpiece 100 from first etchingmodule 330 a and delivers the workpiece 500 into the film-forming module320 a. Adjustments to the controlled environment may be made in transfermodules 310 a and 310 b if film-forming module 320 operates withdifferent parameters than the etching module 330, such as differentvacuum pressures.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 608, with reference to FIGS. 5D,6, and 3, an etch stop layer 520 is deposited over the recessed patternfeatures using one or more of the film-forming modules 320. The etchstop layer 520 may include nitrided films with metals, for exampletantalum nitride, or dielectric materials, for example silicon nitrides.The deposition of the etch stop layer 520 may be performed in the samefilm-forming module as previous operations.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer modules 310 a and 310 b may be used to transfer theworkpiece 500 to the same or a different film-forming module 320 such asfilm-forming module 320 b also hosted on the first common manufacturingplatform 300, e.g., transfer module 310 a removes the workpiece 500 fromfilm-forming module 320 a and transfers it to film-forming module 320 b.Adjustments to the controlled environment may be made in transfermodules 310 a and 310 b if, for example, the second film-forming module320 b operates with different parameters than, for example, the firstfilm module 320 a, such as different vacuum pressures.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 610, with reference to FIGS. 5E,6, and 3, a second dielectric layer of dielectric material is depositedover the etch stop layer 520 using one or more of the film-formingmodules 320, forming an interlayer dielectric film 522. The interlayerdielectric film 522 may include the same material as the underlyinglayer 506. For example, the interlayer dielectric film 522 may includean oxide of silicon. The deposition of the interlayer dielectric film522 may be performed in the same film-forming module as any previousoperation.

Then, in operation 616, with reference to FIGS. 5F, 6, and 3, theworkpiece 500 is transferred to the ancillary module 350 for furtherprocessing. The ancillary module 350 does not operate in the controlledenvironment. The ancillary module 350 may include track module 354 andlithography module 352. The workpiece 100 is transferred from the firstcommon manufacturing platform 300 to the ancillary module 350, leavingthe controlled environment and breaking the vacuum of the first commonmanufacturing platform 300. In some examples, the workpiece 500 istransferred to the track module 354. A photo resist layer 540 is spunonto the upper surface of the workpiece 500, specifically the uppersurface of the interlayer dielectric film 522, in the track module 354.The photo resist layer 540 is a light sensitive layer and is spun ontothe upper surface of the workpiece 500 such that the photo resist layer540 is uniform and covers the upper surface of the workpiece 500, asshown in FIG. 5F.

Then, in operation 618, with further reference to FIGS. 5G, 6, and 3,the workpiece 500 is transferred to the lithography module 352. In someexamples, such as the ancillary module 350 shown in FIG. 3, thelithography module 352 may share a common module, such as the ancillarymodule 350, with the track module 354. Alternatively, the lithographymodule 352 may be a completely or partially separate module from thetrack module 354. In the lithography module 352, a mask (not shown)covers portions of the photo resist layer 540 such that portions notcovered by the mask are exposed. For example, as shown in FIG. 5F, theexposed portion 542 may be left exposed by the mask. The exposed portion542 of the photo resist layer 540 is subjected to light in thelithography module 352. The light weakens the portion of the photoresist layer 540 that the light contacts, namely the exposed portion 542of the photo resist layer 540. The mask covers the remainder of thephoto resist layer 540 and prevents portions other than the exposedportion 542 from being exposed to light in the lithography module 352.Thus, only the exposed portion 542 of the photo resist layer 540 isweakened by exposure to the light in the lithography module 352.

Then, in operation 620, with reference to FIGS. 5G, 6, and 3, theworkpiece 500 is developed in a baking process. The baking processremoves the exposed portion 542 from the workpiece 500. As shown in FIG.5G, the baking process results in the removal of the exposed portion 542(not shown in FIG. 5G because it was removed in the bake) and exposes aportion 544 of the upper surface of the interlayer dielectric film 522.

Then, the workpiece 500 is transferred back to a controlled environment.This controlled environment may be present on a common manufacturingplatform. This common manufacturing platform may be the same ordifferent common manufacturing platform in which operations 602-610 wereperformed, that is the first common manufacturing platform 300.Alternatively, the workpiece 500 may be transferred to the second commonmanufacturing platform 360, which occurs here.

As shown in FIG. 3, the second common manufacturing platform 360includes a front end module (FEM) 362 or a transfer module 370 a thatmay be used to bring the workpiece 100 into the controlled environmentof the second common manufacturing platform 360, which controlledenvironment is maintained throughout at least a portion of the processflow 600. The controlled environment may include a vacuum environment,where at least some operations in the process flow 600 is conductedwithout breaking vacuum, or an inert gas atmosphere, or a combinationthereof. A single transfer module, such as transfer module 370 a, may becoupled between each processing module or tool, or separate transfermodules may be used for each tool transfer. Where different processingmodules on the second common manufacturing platform 360 requiredifferent controlled environments, such as different vacuum pressures orvacuum in one module followed by a module with inert gas atmosphere,multiple transfer modules may be used where the transfer modules assistin implementing the transitions between the different controlledenvironments. While a single transfer module may be useful in acluster-type tool where same-type processing modules are positioned in acircle around the transfer module, multiple transfer modules may be moreappropriate in an end-to-end platform configuration with differentprocessing module types.

A front-end module 362 may be used to load a cassette of workpieces (notshown), sequentially line up the workpieces and insert them into a loadlock, then into a transfer module 370 a in a controlled environment, andthe transfer module 370 a sequentially loads the workpieces into aprocessing module. In the second common manufacturing platform 360, andwith respect to operation 622, the workpiece 500, which has beenreceived into the controlled environment, is loaded by the transfermodule 370 a into an etching module 390, such as first etching module390 b, hosted on the second common manufacturing platform 360 withoutleaving the controlled environment, e.g., without breaking vacuum.Etching modules 390 a, 390 b located on the second common manufacturingplatform 360 may be collectively referred to herein as etching modules390 where appropriate. Similarly, deposition modules 380 a, 380 b may becollectively referred to herein as deposition modules 380 whereappropriate. Adjustments to the controlled environment may be made intransfer module 370 a if etching module 390 operates with differentparameters than the front end module 362, such as different vacuumpressures.

Thereafter, and without leaving the controlled environment, e.g.,without breaking vacuum, in operation 622, with reference to FIGS. 5H,6, and 3, the exposed portion 544 of the interlayer dielectric film 522is etched to form one or more via features 524 a. The via features 524 aare formed by etching the interlayer dielectric film 522 to the etchstop layer 520 using one of the one or more etching modules 330. As aresult, the etch stop layer 520 is exposed at the bottom of the one ormore via features 524 a, as shown in FIG. 5H. Exposure of the etch stoplayer 520 may serve as an indication for the etching module 330 to stopetching deeper into the workpiece 500 toward the substrate 504.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer module 370 a may be used to transfer the workpiece 500to the etching module 390 such as etching module 390 b also hosted onthe second common manufacturing platform 360, e.g., transfer module 370a removes the workpiece 500 from etching module 390 a and delivers theworkpiece 500 into the etching module 330 b. Adjustments to thecontrolled environment may be made in transfer modules 370 a if etchingmodule 390 b operates with different parameters than etching module 390a, such as different vacuum pressures.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, with reference to FIGS. 5I, and 3, the photoresist layer 540 is etched from the upper surface of the interlayerdielectric 522, such as within second etching module 390 b. As a result,the upper surface of the interlayer dielectric 522 is exposed andprepared for deposition of metal feature material.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 624, with reference to FIGS. 5J,6, and 3, the exposed etch stop layer 520 is etched to further form oneor more via features 524 b. The via features 524 b are formed by etchingthe exposed etch stop layer 520 using one of the one or more etchingmodules 390. As a result, at least some of the metal features 510 areexposed at the bottom of the one or more via features 524 b, as shown inFIG. 5J. Exposure of the metal features 510 may serve as an indicationfor the etching module 390 to stop etching deeper into the workpiece 500toward the substrate 504.

Then, without leaving the controlled environment, e.g., without breakingvacuum, transfer modules 370 a may be used to transfer the workpiece 500to the film-forming module 380 such as film-forming module 380 a or 380b also hosted on the second common manufacturing platform 360, e.g.,transfer module 370 a removes the workpiece 500 from etching module 390and delivers the workpiece 500 into the film-forming module 380 a or 380b. Adjustments to the controlled environment may be made in transfermodule 370 a if the film-forming module 380 operates with differentparameters than etching module 390, such as different vacuum pressures.

Thereafter, and again without leaving the controlled environment, e.g.,without breaking vacuum, in operation 626, with reference to FIGS. 5K,6, and 3, a metal 526 is deposited into the via features 524 b using thefilm-forming module 320. The via feature 524 b is filled with the metal526 over the metal features 510 in the film-forming module 320. In someexamples, the metal 526 is selected from the group consisting ofruthenium, tungsten, cobalt, copper, and combinations thereof.

Optionally, the workpiece 500 may be subjected to one or more cleaningprocesses before further patterning operations. For example, cleaningmay be performed in the same cleaning module 340 a, 340 b hosted on thefirst common manufacturing platform 300. A transfer module 310 may beused to transfer the workpiece 500 from the film-forming module 380 to,for example, the first common manufacturing platform 300, and then tothe cleaning module 340. As shown, transfer modules 310 a, 310 b, 370 amay be used to make the transfer. For example, the transfer module 370 amay remove the workpiece from the film-forming module 380 a, andeventually transfer it to the transfer module 310 b, which then deliversthe workpiece into the cleaning module 340. Again, the first commonmanufacturing platform 300 may include two identical cleaning modules340 on the same or opposing sides of the transfer module 310 b. Itshould be understood that second common manufacturing platform 360and/or ancillary module 350 also may include one or more cleaning moduleso that cleaning may be performed therein.

The process flow 600 of FIG. 6 will now be described in detail with theoptional metrology operations. Operation 602 includes receiving theworkpiece into the first common manufacturing platform 300, theworkpiece having a pattern of metal features in a dielectric layerwherein exposed surfaces of the metal features and exposed surfaces ofthe dielectric layer together define an upper planar surface. Operation650 includes optionally performing metrology to obtain measurement datarelated to attributes of the incoming workpiece, such as attributes ofthe metal features, layout of the metal feature pattern, and underlyinglayer within which metal features are formed, which measurement data maybe used to adjust and/or control process parameters of any one ofoperations 602-626.

Operation 604 includes etching the metal features to a predetermineddepth. Operation 652 includes optionally performing metrology to obtainmeasurement data related to attributes of the workpiece having the metalfeatures etched to the predetermined depth, such as attributes of themetal features, the depth of the metal features, and/or the underlyinglayer into which the metal features are formed as affected by the depthof the metal features, which measurement data may be used to adjustand/or control process parameters of any one of operations 602-626 ormay be used to repair the workpiece before continued processing. In oneembodiment, when the measurement data indicates that one or moreattributes do not meet a target condition, the workpiece may betransferred to a correction module to repair the selectively appliedmetal caps. For example, when a depth or uniformity of metal featuresdoes not meet a target depth or uniformity, corrective action may betaken in one or more correction modules, such as further etching of themetal features, metal deposition to raise the metal features, or acombination of two or more thereof.

Operation 606 includes etching the liner layer, using one of the one ormore etching modules. Operation 654 includes optionally performingmetrology to obtain measurement data related to attributes of theworkpiece having the liner layer etched to the predetermined depth, suchas attributes of the liner layer, the depth of the liner layer, and/orthe planarity of the liner layer with an edge of the metal features.Measurement data may be used to adjust and/or control process parametersof any one of operations 602-626 or may be used to repair the workpiecebefore continued processing. In one embodiment, when the measurementdata indicates that one or more attributes do not meet a targetcondition, the workpiece may be transferred to a correction module torepair the selectively applied metal caps. For example, when a depth,uniformity, or planarity of the liner layers does not meet a targetdepth, uniformity, or planarity, corrective action may be taken in oneor more correction modules, such as further etching of the liner layer,liner layer deposition to raise the liner layer, or a combination of twoor more thereof.

Operation 608 depositing an etch stop layer over the recess patternusing one of the one or more film-forming modules. Operation 656includes optionally performing metrology to obtain measurement datarelated to attributes of the workpiece having the etch stop layer formedthereon, such as attributes of the workpiece having the etch stop layerformed thereon, the recess pattern as affected by the etch stop layer,and/or the underlying layer as affected by the etch stop layer, whichmeasurement data may be used to adjust and/or control process parametersof any one of operations 602-626, may be used to make adjustments forsubsequent workpieces to the incoming attributes of the workpieces inoperation 602 or to operations 604-626, or may be used to repair theworkpiece before continued processing. In one embodiment, when themeasurement data indicates that one or more attributes do not meet atarget condition, the workpiece may be transferred to a correctionmodule to repair the etch stop layer over the recess pattern. Forexample, when the thickness, width, or profile of the etch stop layerdoes not meet a target thickness, width, or profile of the etch stoplayer, corrective action may be taken in one or more correction modules,such as by selectively depositing additional material onto the recesspattern, reshaping the etch stop layer, etching a portion of the etchstop layer, or a combination of two or more thereof.

Operation 610 includes depositing a second dielectric material on theetch stop layer to form an interlayer dielectric film over and/or in therecess pattern using one of the one or more film-forming modulesOperation 658 includes optionally performing metrology to obtainmeasurement data related to attributes of the workpiece having thesecond dielectric material, such as attributes of the etch stop layer asaffected by the second dielectric material and/or the underlying layeras affected by the second dielectric material, which measurement datamay be used to adjust and/or control process parameters of operation610, may be used to make adjustments for subsequent workpieces to theincoming attributes of the workpieces in operation 602 or to operations604-626, or may be used to repair the workpiece before continuedprocessing. In one embodiment, when the measurement data indicates thatone or more attributes do not meet a target condition, the workpiece maybe transferred to a correction module to repair the interlayerdielectric film. For example, when the thickness, width, or profile ofthe interlayer dielectric film does not meet a target thickness, width,or profile of the interlayer dielectric film, corrective action may betaken in one or more correction modules, such as by selectivelydepositing additional second dielectric material onto the etch stoplayer, etching the second dielectric material, or a combination of twoor more thereof.

Hereinafter, measurement data may continue to be obtained during thesequence of processing steps related to the formation of the fullyself-aligned via. But here, if measurement data is going to be obtainedutilizing the first common manufacturing platform 300, workpieces willneed to be transferred between platforms 300, 360 and/or ancillarymodule 350. In certain embodiments, it is contemplated that the secondcommon manufacturing platform 360 and/or ancillary module 350 caninclude their own metrology module(s), e.g., metrology module 372 a, andadvantageously include their own “active interdiction system”. In thatinstance, measurement data may continue to be obtained within acontrolled environment at least with respect to the second commonmanufacturing platform 360 and as associated with its own correspondingsequence of processing steps, for example

Operation 616 includes depositing a photo resist layer on the interlayerdielectric film. Operation 668 includes optionally performing metrologyto obtain measurement data related to attributes of the workpiece havingthe photo resist layer deposited thereon, such as attributes of the etchstop layer as affected by the photo resist layer and/or the underlyinglayer as affected by the photo resist layer, which measurement data maybe used to adjust and/or control process parameters of operations 616,may be used to make adjustments for subsequent workpieces to theincoming attributes of the workpieces in operation 602 or to operations604-626, or may be used to repair the workpiece before continuedprocessing. In one embodiment, when the measurement data indicates thatone or more attributes do not meet a target condition, the workpiece maybe transferred to a correction module to repair the photo resist layer.For example, when the thickness, width, uniformity, or profile of thephoto resist layer does not meet a target thickness, width, uniformity,or profile of the interlayer dielectric film, corrective action may betaken in one or more correction modules, such as by selectivelydepositing additional photo resist layer material onto the workpiece,etching the photo resist layer, or a combination of two or more thereof.

Operation 618 includes exposing a photo resist layer to light at leastto weaken the photo resist layer. Operation 670 includes optionallyperforming metrology to obtain measurement data related to attributes ofthe workpiece having the photo resist layer deposited thereon, such asattributes of portions of the photo resist layer as affected by thelight exposure. This measurement data may be used to adjust and/orcontrol process parameters of operations 620, may be used to makeadjustments for subsequent workpieces to the incoming attributes of theworkpieces in operation 602 or to operations 604-626, or may be used torepair the workpiece before continued processing. In one embodiment,when the measurement data indicates that one or more attributes do notmeet a target condition, the workpiece may be transferred to acorrection module to repair the photo resist layer. For example, whenthe specific portions or desired weakness of the photo resist layer doesnot meet a target specific portions or desired weakness of the photoresist layer, corrective action may be taken in one or more correctionmodules, such as by selectively depositing additional photo resist layermaterial onto the workpiece, etching the photo resist layer, furtherexposing portions of the photo resist layer to light, or a combinationof two or more thereof.

Operation 620 includes baking or developing a portion of the photoresist layer on the interlayer dielectric film. Operation 672 includesoptionally performing metrology to obtain measurement data related toattributes of the workpiece having the photo resist layer depositedthereon, such as attributes of the photo resist layer and/or attributesof the interlayer dielectric film as affected by the photo resist layer,which measurement data may be used to adjust and/or control processparameters of operations 620, may be used to make adjustments forsubsequent workpieces to the incoming attributes of the workpieces inoperation 602 or to operations 604-626, or may be used to repair theworkpiece before continued processing. In one embodiment, when themeasurement data indicates that one or more attributes do not meet atarget condition, the workpiece may be transferred to a correctionmodule to repair the photo resist layer. For example, when the portionsof the photo resist layer removed in the baking/development process donot meet a target portion removed, corrective action may be taken in oneor more correction modules, such as by selectively depositing additionalphoto resist layer material onto the workpiece, etching the photo resistlayer, further exposing portions of the photo resist layer to light, ora combination of two or more thereof.

Operation 622 includes etching one or more via features through theinterlayer dielectric to the etch stop layer using one of the one ormore etching modules, the etch stop layer exposed at a bottom of the oneor more via features and/or etching the photo resist layer from theinterlayer dielectric film. Operation 664 includes optionally performingmetrology to obtain measurement data related to attributes of theworkpiece having the etched via features though the interlayerdielectric film, such as attributes of the etch stop layer as affectedby the interlayer dielectric film material and/or the underlying layeras affected by the interlayer dielectric film material, whichmeasurement data may be used to adjust and/or control process parametersof operation 622, may be used to make adjustments for subsequentworkpieces to the incoming attributes of the workpieces in operation 602or to operations 604-626, or may be used to repair the workpiece beforecontinued processing. In one embodiment, when the measurement dataindicates that one or more attributes do not meet a target condition,the workpiece may be transferred to a correction module to repair theinterlayer dielectric film. For example, when the thickness, width, orprofile of the interlayer dielectric film does not meet a targetthickness, width, or profile of the interlayer dielectric film,corrective action may be taken in one or more correction modules, suchas by selectively depositing additional second dielectric material ontothe etch stop layer, etching the second dielectric material, or acombination of two or more thereof.

Operation 624 includes etching the exposed etch stop layer at the bottomof the one or more via features using one of the one or more etchingmodules to expose the metal caps at the bottom of the one or more viafeatures. Operation 672 includes optionally performing metrology toobtain measurement data related to attributes of the workpiece havingthe etched via features though the etch stop layer, such as attributesof the etch stop layer as affected by the exposure of the metal capand/or the underlying layer as affected by the exposure of the metalcap, which measurement data may be used to adjust and/or control processparameters of operation 624, may be used to make adjustments forsubsequent workpieces to the incoming attributes of the workpieces inoperation 602 or to operations 604-626, or may be used to repair theworkpiece before continued processing. In one embodiment, when themeasurement data indicates that one or more attributes do not meet atarget condition, the workpiece may be transferred to a correctionmodule to repair the via feature through the etch stop layer. Forexample, when the thickness, width, or profile of the via featurethrough the etch stop layer does not meet a target depth, width, orprofile of the via feature, corrective action may be taken in one ormore correction modules, such as by etching the etch stop layer.

Operation 626 includes filling the one or more via features over themetal caps with a metal using one of the one or more film-formingmodules. Operation 626 may further include optionally performingmetrology to obtain measurement data related to attributes of theworkpiece having via feature filled over the metal caps, such asattributes of the via feature as affected by filling the one or more viafeatures over the metal caps and/or the underlying layer as affected byfilling the one or more via features over the metal caps, whichmeasurement data may be used to adjust and/or control process parametersof operation 626, may be used to make adjustments for subsequentworkpieces to the incoming attributes of the workpieces in operation 602or to operations 604-626, or may be used to repair the workpiece beforecontinued processing. In one embodiment, when the measurement dataindicates that one or more attributes do not meet a target condition,the workpiece may be transferred to a correction module to repair thefilling of the via feature. For example, when the thickness, width, orprofile of the filled via feature does not meet a target depth, width,or profile of the via feature, corrective action may be taken in one ormore correction modules, such as by depositing additional metal into thevia feature, etching an overburdened filled via feature, or acombination of two or more thereof.

Process parameters, as referred to above, may include any operatingvariable within a processing module, such as but not limited to: gasflow rates; compositions of etchants, deposition reactants, purge gases,etc.; chamber pressure; temperature; electrode spacing; power; etc. Theintelligence system of the active interdiction system is configured togather measurement data from the inspection system and control theintegrated sequence of processing steps executed on the commonmanufacturing platform, for example, by making in situ adjustments toprocessing parameters in subsequent processing modules for the workpiecein process, or by changing process parameters in one or more processingmodules for subsequent workpieces. Thus, the obtained measurement datamay be used to identify a needed repair to the workpiece during theintegrated sequence of processing steps to avoid having to scrap theworkpiece, and/or to adjust processing parameters for the integratedsequence of processing steps for steps performed on the same workpieceafter the measurement data is obtained or for processing subsequentworkpieces to reduce occurrences of the target conditions not being metfor the subsequent workpieces.

Additional advantages and modifications will readily appear to thoseskilled in the art. The invention in its broader aspects is thereforenot limited to the specific details, representative apparatus andmethod, and illustrative examples shown and described. Accordingly,departures may be made from such details without departing from thescope of the general inventive concept.

What we claim:
 1. A method of preparing for a self-aligned via on asemiconductor workpiece comprising: using an integrated sequence ofprocessing steps executed on a common manufacturing platform hosting aplurality of processing modules including one or more film-formingmodules, one or more etching modules, and one or more transfer modules,the integrated sequence of processing steps comprising: receiving theworkpiece into the common manufacturing platform, the workpiece having apattern of metal features in a dielectric layer wherein exposed surfacesof the metal features and exposed surfaces of the dielectric layertogether define an upper planar surface; selectively depositing metalcaps on the exposed surfaces of the metal features relative to theexposed dielectric material using one of the one or more of thefilm-forming modules; selectively forming a recessed pattern ofdielectric material around the metal features relative to the dielectricmaterial, with the metal caps forming a bottom surface of the recessedpattern, the metal caps being exposed from the top of the trench; andinspecting the workpiece at one or more points of the integratedsequence to detect a non-conformity on the workpiece related to themetal cap deposition and/or recessed pattern formation, wherein theintegrated sequence of processing steps is executed in a controlledenvironment within the common manufacturing platform and without leavingthe controlled environment, and wherein the one or more transfer modulesare used to transfer the workpiece between the plurality of processingmodules while maintaining the workpiece within the controlledenvironment.
 2. The method of claim 1, wherein selectively forming therecessed pattern comprises: depositing a self-assembled monolayer on themetal caps using one of the one or more film-forming modules;selectively depositing a first dielectric material on the exposedsurfaces of the dielectric layer using one of the one or morefilm-forming modules to form a recess in the first dielectric material;and etching the workpiece to remove the self-assembled monolayer usingone of the one or more etching modules to expose the metal caps atbottom surfaces of the trench pattern;
 3. The method of claim 2, furthercomprising: depositing an etch stop layer over the recess pattern usingone of the one or more film-forming modules; and depositing a seconddielectric material on the etch stop layer to form an interlayerdielectric over the recess pattern using one of the one or morefilm-forming modules.
 4. The method of claim 2, wherein inspecting theworkpiece at one or more points of the integrated sequence to detect anon-conformity on the workpiece comprises obtaining measurement datarelated to the metal caps and/or of the exposed surfaces of thedielectric layer to verify that the metal caps are covered by theself-assembled monolayer above a pre-determined monolayer coveragethreshold and/or metal nuclei on the exposed surfaces of the dielectriclayer is above a predetermined metal nuclei threshold.
 5. The method ofclaim 4, further comprising implementing a remedial action to amelioratethe non-conformity when the measurement data indicates thenon-conformity is present on the workpiece, the remedial actioncomprises removing the self-assembled monolayer when the pre-determinedmonolayer coverage threshold is exceeded and/or removing metal nucleifrom the dielectric layer when the predetermined metal nuclei thresholdis exceeded.
 6. The method of claim 2, wherein inspecting the workpieceat one or more points of the integrated sequence to detect anon-conformity on the workpiece comprises: obtaining measurement datarelated to attributes of the metal caps to verify that theself-assembled monolayer is removed from the metal caps; or obtainingmeasurement data related to attributes of the first dielectric materialto verify that the first dielectric material completely covers theexposed surfaces of the dielectric layer and/or to verify an absence ofthe first dielectric layer on the exposed surfaces of the metal caps. 7.The method of claim 6, further comprising implementing a remedial actionto ameliorate the non-conformity when the measurement data indicates thenon-conformity is present on the workpiece, the remedial actioncomprises removing self-assembled monolayer from the metals caps based,at least in part, the measurement data related to attributes of themetal caps and/or removing the first dielectric layer from the exposedsurfaces of the metal caps based, at least in part, on measurement datarelated to attributes of the first dielectric material.
 8. The method ofclaim 1, wherein the metal caps comprise ruthenium, cobalt, tungsten, ormolybdenum.
 9. A method of preparing for a self-aligned via on asemiconductor workpiece comprising: using an integrated sequence ofprocessing steps executed on a common manufacturing platform hosting aplurality of processing modules including one or more film-formingmodules, one or more etching modules, and one or more transfer modules,the integrated sequence of processing steps comprising: receiving theworkpiece into the common manufacturing platform, the workpiece having apattern of metal features in a dielectric layer wherein exposed surfacesof the metal features and exposed surfaces of the dielectric layertogether define an upper planar surface; selectively etching the metalfeatures to form a recess pattern by recessing the exposed surfaces ofthe metal features beneath the exposed surfaces of the dielectric layerusing one of the one or more etching modules; depositing an etch stoplayer over the recess pattern using one of the one or more film-formingmodules; and inspecting the workpiece at one or more points of theintegrated sequence to detect a non-conformity on the workpiece relatedto the etch stop layer deposition and/or recessed pattern formation,wherein the integrated sequence of processing steps is executed in acontrolled environment within the common manufacturing platform andwithout leaving the controlled environment, and wherein the one or moretransfer modules are used to transfer the workpiece between theplurality of processing modules while maintaining the workpiece withinthe controlled environment.
 10. The method of claim 9, wherein the metalfeatures comprise a ruthenium film layer and liner film layer disposedbetween the ruthenium film layer and the workpiece.
 11. The method ofclaim 9, wherein the metal features comprise ruthenium, cobalt,tungsten, or molybdenum.
 12. A method of forming a self-aligned via on asemiconductor workpiece, the method comprising: receiving the workpiececomprising a pattern of metal features in a dielectric layer whereinexposed surfaces of the metal features and exposed surfaces of thedielectric layer together define an upper planar surface; selectivelydepositing metal caps on the exposed surfaces of the metal featuresrelative to the exposed dielectric material, the selectivity between themetal cap and the dielectric material being based, at least in part, ona higher metal cap layer deposition rate on the metal features than onthe dielectric material; selectively forming a barrier layer on themetal caps relative to the exposed dielectric material; the selectivitybetween the metal cap and the dielectric material being based, at leastin part, on a higher barrier layer deposition rate on the metal capsthan on the dielectric material; selectively depositing a firstdielectric material on the exposed surfaces of the dielectric layer toform a recess pattern in the first dielectric material, the selectivedeposition being based, at least in part, on a deposition rate of thefirst dielectric material being higher on the exposed surfaces than onthe metal caps, the recess pattern comprising a sidewall including aportion of the first dielectric material; treating the workpiece toexpose the metal caps at bottom surfaces of the recess pattern; anddepositing an etch stop layer over the recess pattern.
 13. The method ofclaim 12, wherein the selective deposition comprises two or moredeposition steps which apply 10 nm or less of the first dielectricmaterial on the workpiece.
 14. The method of claim 12, furthercomprising pre-treating the workpiece before depositing the metal capsto alter a surface termination of the first dielectric material, andwherein the pretreating is done in one or more pre-treatment modules onthe common manufacturing platform.
 15. The method of claim 12, furthercomprising removing any metal from the first dielectric material, usingthe one-or-more etching chambers, during the metal cap deposition step.16. The method of claim 12, further comprising removing the firstdielectric material from the barrier layer or metal caps during or afterthe first dielectric material deposition step.
 17. The method of claim12, further comprising removing the first dielectric material and/or thebarrier layer from the metal caps after the first dielectric materialdeposition step.
 18. The method of claim 11, further comprisingselectively forming a replacement barrier layer on the metal capsrelative to the exposed dielectric material, the selectivity between themetal cap and the dielectric material being based, at least in part, ona higher replacement barrier layer deposition rate on the metal capsthan on the dielectric material.
 19. The method of claim 12, wherein themetal caps comprise ruthenium, cobalt, tungsten, or molybdenum.